@ohos.data.distributedKVStore (Distributed KV Store)

The distributedKVStore module implements collaboration between databases for different devices that forms a Super Device. You can use the APIs provided by this module to save application data to a distributed key-value (KV) store and perform operations, such as adding, deleting, modifying, querying, and synchronizing data in distributed KV stores.

The distributedKVStore module provides the following functions:

• KVManager: provides a KVManager instance to obtain KV store information.
• KVStoreResultSet: provides APIs for accessing the results obtained from a KV store.
• Query: provides APIs for setting predicates for data query.
• SingleKVStore: provides APIs for querying and synchronizing data in single KV stores. The single KV stores manage data without distinguishing devices.
• DeviceKVStore: provides APIs for querying and synchronizing data in device KV stores. This class inherits from SingleKVStore. The device KV stores manage data by device.

NOTE

The initial APIs of this module are supported since API version 9. Newly added APIs will be marked with a superscript to indicate their earliest API version.

Modules to Import

import distributedKVStore from '@ohos.data.distributedKVStore';

KVManagerConfig

Provides the KVManager instance configuration, including the bundle name of the invoker and the application context.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Name	Type	Mandatory	Description
context	Context	Yes	Application context. For details about the application context of the FA model, see Context. For details about the application context of the stage model, see Context. Since API version 10, the type of context is BaseContext.
bundleName	string	Yes	Bundle name.

Constants

Provides constants of the distributed KV store.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Name	Value	Description
MAX_KEY_LENGTH	1024	Maximum length of a key in a distributed KV store, in bytes.
MAX_VALUE_LENGTH	4194303	Maximum length of a value in a distributed KV store, in bytes.
MAX_KEY_LENGTH_DEVICE	896	Maximum length of a key in a device KV store, in bytes.
MAX_STORE_ID_LENGTH	128	Maximum length of a KV store ID, in bytes.
MAX_QUERY_LENGTH	512000	Maximum query length, in bytes.
MAX_BATCH_SIZE	128	Maximum number of batch operations.

ValueType

Enumerates the types of the value in a KV pair.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Name	Description
STRING	String.
INTEGER	Integer.
FLOAT	Float (single-precision floating point).
BYTE_ARRAY	Byte array.
BOOLEAN	Boolean.
DOUBLE	Double (double-precision floating point).

Value

Defines the value object in a KV store.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Name	Type	Mandatory	Description
type	ValueType	Yes	Type of the value.
value	Uint8Array |string |number |boolean	Yes	Value of the KV pair.

Entry

Defines the KV pairs stored in a KV store.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Name	Type	Mandatory	Description
key	string	Yes	Key of a KV pair in the KV store.
value	Value	Yes	Value of a KV pair in the KV store.

ChangeNotification

Defines the content of a data change notification, including inserted data, updated data, deleted data, and device ID.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Name	Type	Mandatory	Description
insertEntries	Entry[]	Yes	Data inserted.
updateEntries	Entry[]	Yes	Data updated.
deleteEntries	Entry[]	Yes	Data deleted.
deviceId	string	Yes	UUID of the device.

SyncMode

Enumerates the synchronization modes.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Name	Description
PULL_ONLY	Pull data from the peer end to the local end only.
PUSH_ONLY	Push data from the local end to the peer end only.
PUSH_PULL	Push data from the local end to the peer end and then pull data from the peer end to the local end.

SubscribeType

Enumerates the subscription types.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Name	Description
SUBSCRIBE_TYPE_LOCAL	Local data changes.
SUBSCRIBE_TYPE_REMOTE	Remote data changes.
SUBSCRIBE_TYPE_ALL	Local and remote data changes.

KVStoreType

Enumerates the distributed KV store types.

Name	Description
DEVICE_COLLABORATION	Device KV store. The device KV store manages data by device, which eliminates conflicts. Data can be queried by device. System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore
SINGLE_VERSION	Single KV store. The single KV store does not differentiate data by device. If entries with the same key are modified on different devices, the value will be overwritten. System capability: SystemCapability.DistributedDataManager.KVStore.Core

SecurityLevel

Enumerates the KV store security levels.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Name	Description
S1	Low security level. Disclosure, tampering, corruption, or loss of the data may cause minor impact on an individual or group. Examples: gender and nationality information, and user application records
S2	Medium security level. Disclosure, tampering, corruption, or loss of the data may cause major impact on an individual or group. Examples: mailing addresses and nicknames of individuals
S3	High security level. Disclosure, tampering, corruption, or loss of the data may cause critical impact on an individual or group. Examples: real-time precise positioning information and movement trajectory
S4	Critical security level. Disclosure, tampering, corruption, or loss of the data may cause significant adverse impact on an individual or group. Examples: political opinions, religious and philosophical belief, trade union membership, genetic data, biological information, health and sexual life status, sexual orientation, device authentication, and personal credit card information

Options

Provides KV store configuration.

Name	Type	Mandatory	Description
createIfMissing	boolean	No	Whether to create a KV store if the database file does not exist. The default value is true, which means to create a KV store. System capability: SystemCapability.DistributedDataManager.KVStore.Core
encrypt	boolean	No	Whether to encrypt the KV store. The default value is false, which means the KV store is not encrypted. System capability: SystemCapability.DistributedDataManager.KVStore.Core
backup	boolean	No	Whether to back up the KV store. The default value is true, which means to back up the KV store. System capability: SystemCapability.DistributedDataManager.KVStore.Core
autoSync	boolean	No	Whether to automatically synchronize database files. The default value is false, which means the database files are manually synchronized. System capability: SystemCapability.DistributedDataManager.KVStore.Core Required permissions: ohos.permission.DISTRIBUTED_DATASYNC
kvStoreType	KVStoreType	No	Type of the KV store to create. The default value is DEVICE_COLLABORATION, which indicates a device KV store. System capability: SystemCapability.DistributedDataManager.KVStore.Core
securityLevel	SecurityLevel	Yes	Security level of the KV store. System capability: SystemCapability.DistributedDataManager.KVStore.Core
schema	Schema	No	Schema used to define the values stored in the KV store. The default value is undefined, which means no schema is used. System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Schema

Defines the schema of a KV store. You can create a Schema object and place it in Options when creating or opening a KV store.

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Name	Type	Readable	Writable	Description
root	FieldNode	Yes	Yes	JSON root object.
indexes	Array<string>	Yes	Yes	String array in JSON format.
mode	number	Yes	Yes	Schema mode.
skip	number	Yes	Yes	Size of a skip of the schema.

constructor

constructor()

A constructor used to create a Schema instance.

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

FieldNode

Represents a Schema instance, which provides the methods for defining the values stored in a KV store.

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Name	Type	Readable	Writable	Description
nullable	boolean	Yes	Yes	Whether the database field can be null.
default	string	Yes	Yes	Default value of a FieldNode.
type	number	Yes	Yes	Value of the data type corresponding to the specified node.

constructor

constructor(name: string)

A constructor used to create a FieldNode instance with a string field.

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Name	Type	Mandatory	Description
name	string	Yes	Value of FieldNode.

appendChild

appendChild(child: FieldNode): boolean

Appends a child node to this FieldNode.

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Name	Type	Mandatory	Description
child	FieldNode	Yes	Child node to append.

Return value

Type	Description
boolean	Returns true if the operation is successful; returns false otherwise.

Example

try {
  let node: distributedKVStore.FieldNode|null = new distributedKVStore.FieldNode("root");
  let child1: distributedKVStore.FieldNode|null = new distributedKVStore.FieldNode("child1");
  let child2: distributedKVStore.FieldNode|null = new distributedKVStore.FieldNode("child2");
  let child3: distributedKVStore.FieldNode|null = new distributedKVStore.FieldNode("child3");
  node.appendChild(child1);
  node.appendChild(child2);
  node.appendChild(child3);
  console.info("appendNode " + JSON.stringify(node));
  child1 = null;
  child2 = null;
  child3 = null;
  node = null;
} catch (e) {
  console.error("AppendChild " + e);
}

distributedKVStore.createKVManager

createKVManager(config: KVManagerConfig): KVManager

Creates a KVManager instance for KV store management.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
config	KVManagerConfig	Yes	KVManager instance configuration, including the bundle name and user information of the caller.

Return value

Type	Description
KVManager	KVManager instance created.

Example

Stage model:

import UIAbility from '@ohos.app.ability.UIAbility';
import { BusinessError } from '@ohos.base';

let kvManager: distributedKVStore.KVManager;

export default class EntryAbility extends UIAbility {
  onCreate() {
    console.info("MyAbilityStage onCreate")
    let context = this.context
    const kvManagerConfig: distributedKVStore.KVManagerConfig = {
      context: context,
      bundleName: 'com.example.datamanagertest',
    }
    try {
      kvManager = distributedKVStore.createKVManager(kvManagerConfig);
      console.info("Succeeded in creating KVManager");
    } catch (e) {
      let error = e as BusinessError;
      console.error(`Failed to create KVManager.code is ${error.code},message is ${error.message}`);
    }
  }
}

FA model:

import featureAbility from '@ohos.ability.featureAbility';
import { BusinessError } from '@ohos.base';

let kvManager: distributedKVStore.KVManager;
let context = featureAbility.getContext()
const kvManagerConfig: distributedKVStore.KVManagerConfig = {
  context: context,
  bundleName: 'com.example.datamanagertest',
}
try {
  kvManager = distributedKVStore.createKVManager(kvManagerConfig);
  console.info("Succeeded in creating KVManager");
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to create KVManager.code is ${error.code},message is ${error.message}`);
}

KVManager

Provides an instance to obtain information about a distributed KV store. Before calling any API in KVManager, you must use createKVManager to create a KVManager instance.

getKVStore

getKVStore<T>(storeId: string, options: Options, callback: AsyncCallback<T>): void

Creates and obtains a distributed KV store. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
storeId	string	Yes	Unique identifier of the KV store. The length cannot exceed MAX_STORE_ID_LENGTH.
options	Options	Yes	Configuration of the KV store to create.
callback	AsyncCallback<T>	Yes	Callback invoked to return the SingleKVStore or DeviceKVStore instance created.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100002	Open existed database with changed options.
15100003	Database corrupted.

Example

import { BusinessError } from '@ohos.base';

let kvManager: distributedKVStore.KVManager = xxx;
let kvStore: distributedKVStore.SingleKVStore|null;
try {
  const options: distributedKVStore.Options = {
    createIfMissing: true,
    encrypt: false,
    backup: false,
    autoSync: true,
    kvStoreType: distributedKVStore.KVStoreType.SINGLE_VERSION,
    securityLevel: distributedKVStore.SecurityLevel.S2,
  };
  kvManager.getKVStore('storeId', options, (err, store: distributedKVStore.SingleKVStore) => {
    if (err) {
      console.error(`Failed to get KVStore.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info("Succeeded in getting KVStore");
    kvStore = store;
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

getKVStore

getKVStore<T>(storeId: string, options: Options): Promise<T>

Creates and obtains a distributed KV store. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
storeId	string	Yes	Unique identifier of the KV store. The length cannot exceed MAX_STORE_ID_LENGTH.
options	Options	Yes	Configuration of the distributed KV store to create.

Return value

Type	Description
Promise<T>	Promise used to return the SingleKVStore or DeviceKVStore instance created.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100002	Open existed database with changed options.
15100003	Database corrupted.

Example

import { BusinessError } from '@ohos.base';

let kvManager: distributedKVStore.KVManager = xxx;
let kvStore: distributedKVStore.SingleKVStore|null;
try {
  const options: distributedKVStore.Options = {
    createIfMissing: true,
    encrypt: false,
    backup: false,
    autoSync: true,
    kvStoreType: distributedKVStore.KVStoreType.SINGLE_VERSION,
    securityLevel: distributedKVStore.SecurityLevel.S2,
  };
  kvManager.getKVStore<distributedKVStore.SingleKVStore>('storeId', options).then((store: distributedKVStore.SingleKVStore) => {
    console.info("Succeeded in getting KVStore");
    kvStore = store;
  }).catch((err: BusinessError) => {
    console.error(`Failed to get KVStore.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

closeKVStore

closeKVStore(appId: string, storeId: string, callback: AsyncCallback<void>): void

Closes a distributed KV store. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
appId	string	Yes	Bundle name of the app that invokes the KV store.
storeId	string	Yes	Unique identifier of the KV store to close. The length cannot exceed MAX_STORE_ID_LENGTH.
callback	AsyncCallback<void>	Yes	Callback invoked to return the result.

Example

import { BusinessError } from '@ohos.base';

let kvManager: distributedKVStore.KVManager = xxx;
let kvStore: distributedKVStore.SingleKVStore|null;
const options: distributedKVStore.Options = {
  createIfMissing: true,
  encrypt: false,
  backup: false,
  autoSync: true,
  kvStoreType: distributedKVStore.KVStoreType.SINGLE_VERSION,
  schema: undefined,
  securityLevel: distributedKVStore.SecurityLevel.S2,
}
try {
  kvManager.getKVStore('storeId', options, async (err, store: distributedKVStore.SingleKVStore|null) => {
    if (err != undefined) {
      console.error(`Failed to get KVStore.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in getting KVStore');
    kvStore = store;
    kvStore = null;
    store = null;
    kvManager.closeKVStore('appId', 'storeId', (err)=> {
      if (err != undefined) {
        console.error(`Failed to close KVStore.code is ${err.code},message is ${err.message}`);
        return;
      }
      console.info('Succeeded in closing KVStore');
    });
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

closeKVStore

closeKVStore(appId: string, storeId: string): Promise<void>

Closes a distributed KV store. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
appId	string	Yes	Bundle name of the app that invokes the KV store.
storeId	string	Yes	Unique identifier of the KV store to close. The length cannot exceed MAX_STORE_ID_LENGTH.

Return value

Type	Description
Promise<void>	Promise that returns no value.

Example

import { BusinessError } from '@ohos.base';

let kvManager: distributedKVStore.KVManager = xxx;
let kvStore: distributedKVStore.SingleKVStore|null;

const options: distributedKVStore.Options = {
  createIfMissing: true,
  encrypt: false,
  backup: false,
  autoSync: true,
  kvStoreType: distributedKVStore.KVStoreType.SINGLE_VERSION,
  schema: undefined,
  securityLevel: distributedKVStore.SecurityLevel.S2,
}
try {
  kvManager.getKVStore<distributedKVStore.SingleKVStore>('storeId', options).then(async (store: distributedKVStore.SingleKVStore|null) => {
    console.info('Succeeded in getting KVStore');
    kvStore = store;
    kvStore = null;
    store = null;
    kvManager.closeKVStore('appId', 'storeId').then(() => {
      console.info('Succeeded in closing KVStore');
    }).catch((err: BusinessError) => {
      console.error(`Failed to close KVStore.code is ${err.code},message is ${err.message}`);
    });
  }).catch((err: BusinessError) => {
    console.error(`Failed to get KVStore.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to close KVStore.code is ${error.code},message is ${error.message}`);
}

deleteKVStore

deleteKVStore(appId: string, storeId: string, callback: AsyncCallback<void>): void

Deletes a distributed KV store. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
appId	string	Yes	Bundle name of the app that invokes the KV store.
storeId	string	Yes	Unique identifier of the KV store to delete. The length cannot exceed MAX_STORE_ID_LENGTH.
callback	AsyncCallback<void>	Yes	Callback invoked to return the result.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100004	Not found.

Example

import { BusinessError } from '@ohos.base';

let kvManager: distributedKVStore.KVManager = xxx;
let kvStore: distributedKVStore.SingleKVStore|null;

const options: distributedKVStore.Options = {
  createIfMissing: true,
  encrypt: false,
  backup: false,
  autoSync: true,
  kvStoreType: distributedKVStore.KVStoreType.SINGLE_VERSION,
  schema: undefined,
  securityLevel: distributedKVStore.SecurityLevel.S2,
}
try {
  kvManager.getKVStore('store', options, async (err, store: distributedKVStore.SingleKVStore|null) => {
    if (err != undefined) {
      console.error(`Failed to get KVStore.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in getting KVStore');
    kvStore = store;
    kvStore = null;
    store = null;
    kvManager.deleteKVStore('appId', 'storeId', (err) => {
      if (err != undefined) {
        console.error(`Failed to delete KVStore.code is ${err.code},message is ${err.message}`);
        return;
      }
      console.info(`Succeeded in deleting KVStore`);
    });
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to delete KVStore.code is ${error.code},message is ${error.message}`);
}

deleteKVStore

deleteKVStore(appId: string, storeId: string): Promise<void>

Deletes a distributed KV store. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
appId	string	Yes	Bundle name of the app that invokes the KV store.
storeId	string	Yes	Unique identifier of the KV store to delete. The length cannot exceed MAX_STORE_ID_LENGTH.

Return value

Type	Description
Promise<void>	Promise that returns no value.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100004	Not found.

Example

import { BusinessError } from '@ohos.base';

let kvManager: distributedKVStore.KVManager = xxx;
let kvStore: distributedKVStore.SingleKVStore|null;

const options: distributedKVStore.Options = {
  createIfMissing: true,
  encrypt: false,
  backup: false,
  autoSync: true,
  kvStoreType: distributedKVStore.KVStoreType.SINGLE_VERSION,
  schema: undefined,
  securityLevel: distributedKVStore.SecurityLevel.S2,
}
try {
  kvManager.getKVStore<distributedKVStore.SingleKVStore>('storeId', options).then(async (store: distributedKVStore.SingleKVStore|null) => {
    console.info('Succeeded in getting KVStore');
    kvStore = store;
    kvStore = null;
    store = null;
    kvManager.deleteKVStore('appId', 'storeId').then(() => {
      console.info('Succeeded in deleting KVStore');
    }).catch((err: BusinessError) => {
      console.error(`Failed to delete KVStore.code is ${err.code},message is ${err.message}`);
    });
  }).catch((err: BusinessError) => {
    console.error(`Failed to get KVStore.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to delete KVStore.code is ${error.code},message is ${error.message}`);
}

getAllKVStoreId

getAllKVStoreId(appId: string, callback: AsyncCallback<string[]>): void

Obtains the IDs of all distributed KV stores that are created by getKVStore and have not been deleted by deleteKVStore. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
appId	string	Yes	Bundle name of the app that invokes the KV store.
callback	AsyncCallback<string[]>	Yes	Callback invoked to return the IDs of all the distributed KV stores created.

Example

import { BusinessError } from '@ohos.base';

let kvManager: distributedKVStore.KVManager = xxx;

try {
  kvManager.getAllKVStoreId('appId', (err, data) => {
    if (err != undefined) {
      console.error(`Failed to get AllKVStoreId.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in getting AllKVStoreId');
    console.info(`GetAllKVStoreId size = ${data.length}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to get AllKVStoreId.code is ${error.code},message is ${error.message}`);
}

getAllKVStoreId

getAllKVStoreId(appId: string): Promise<string[]>

Obtains the IDs of all distributed KV stores that are created by getKVStore and have not been deleted by deleteKVStore. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
appId	string	Yes	Bundle name of the app that invokes the KV store.

Return value

Type	Description
Promise<string[]>	Promise used to return the IDs of all the distributed KV stores created.

Example

import { BusinessError } from '@ohos.base';

let kvManager: distributedKVStore.KVManager = xxx;

try {
  console.info('GetAllKVStoreId');
  kvManager.getAllKVStoreId('appId').then((data: string[]) => {
    console.info('Succeeded in getting AllKVStoreId');
    console.info(`GetAllKVStoreId size = ${data.length}`);
  }).catch((err: BusinessError) => {
    console.error(`Failed to get AllKVStoreId.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to get AllKVStoreId.code is ${error.code},message is ${error.message}`);
}

on(‘distributedDataServiceDie’)

on(event: ‘distributedDataServiceDie’, deathCallback: Callback<void>): void

Subscribes to service status changes. If the service is terminated, you need to register the callbacks for data change notifications and synchronization complete notifications again. In addition, an error will be returned for a synchronization operation.

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Name	Type	Mandatory	Description
event	string	Yes	Event to subscribe to. The value is distributedDataServiceDie, which indicates a service status change event.
deathCallback	Callback<void>	Yes	Callback invoked to return service status changes.

Example

import { BusinessError } from '@ohos.base';

let kvManager: distributedKVStore.KVManager = xxx;

try {
  console.info('KVManagerOn');
  const deathCallback = () => {
    console.info('death callback call');
  }
  kvManager.on('distributedDataServiceDie', deathCallback);
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

off(‘distributedDataServiceDie’)

off(event: ‘distributedDataServiceDie’, deathCallback?: Callback<void>): void

Unsubscribes from service status changes. The deathCallback parameter must be a callback registered for subscribing to service status changes. Otherwise, the unsubscription will fail.

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Name	Type	Mandatory	Description
event	string	Yes	Event to unsubscribe from. The value is distributedDataServiceDie, which indicates a service status change event.
deathCallback	Callback<void>	No	Callback for the service status change event. If this parameter is not specified, all subscriptions to the service status change event will be canceled.

Example

import { BusinessError } from '@ohos.base';

let kvManager: distributedKVStore.KVManager = xxx;

try {
  console.info('KVManagerOff');
  const deathCallback = () => {
    console.info('death callback call');
  }
  kvManager.off('distributedDataServiceDie', deathCallback);
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

KVStoreResultSet

Provides APIs for obtaining the distributed KV store result sets. A maximum of eight result sets can be opened at a time.

Before calling any API in KVStoreResultSet, you must use getKVStore to construct a SingleKVStore or DeviceKVStore instance.

getCount

getCount(): number

Obtains the total number of rows in the result set.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Type	Description
number	Total number of rows obtained.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  let count: number;
  kvStore.getResultSet('batch_test_string_key').then((result) => {
    console.info('getResultSet succeed.');
    resultSet = result;
    count = resultSet.getCount();
    console.info("getCount succeed:" + count);
  }).catch((err: BusinessError) => {
    console.error('getResultSet failed: ' + err);
  });
} catch (e) {
  console.error("getCount failed: " + e);
}

getPosition

getPosition(): number

Obtains the current data read position (position from which data is read) in the result set. The read position changes with the operations, such as moveToFirst and moveToLast.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Type	Description
number	Current data read position obtained. The value must be greater than or equal to -1. The value -1 means no data is read; the value 0 indicates the first row.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  let position: number;
  kvStore.getResultSet('batch_test_string_key').then((result) => {
    console.info('getResultSet succeeded.');
    resultSet = result;
    position = resultSet.getPosition();
    console.info("getPosition succeed:" + position);
  }).catch((err: BusinessError) => {
    console.error('getResultSet failed: ' + err);
  });
} catch (e) {
  console.error("getPosition failed: " + e);
}

moveToFirst

moveToFirst(): boolean

Moves the data read position to the first row. If the result set is empty, false will be returned.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Type	Description
boolean	Returns true if the operation is successful; returns false otherwise.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  let moved: boolean;
  kvStore.getResultSet('batch_test_string_key').then((result) => {
    console.info('getResultSet succeed.');
    resultSet = result;
    moved = resultSet.moveToFirst();
    console.info("moveToFirst succeed: " + moved);
  }).catch((err: BusinessError) => {
    console.error('getResultSet failed: ' + err);
  });
} catch (e) {
  console.error("moveToFirst failed " + e);
}

moveToLast

moveToLast(): boolean

Moves the data read position to the last row. If the result set is empty, false will be returned.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Type	Description
boolean	Returns true if the operation is successful; returns false otherwise.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  let moved: boolean;
  kvStore.getResultSet('batch_test_string_key').then((result) => {
    console.info('getResultSet succeed.');
    resultSet = result;
    moved = resultSet.moveToLast();
    console.info("moveToLast succeed:" + moved);
  }).catch((err: BusinessError) => {
    console.error('getResultSet failed: ' + err);
  });
} catch (e) {
  console.error("moveToLast failed: " + e);
}

moveToNext

moveToNext(): boolean

Moves the data read position to the next row. If the result set is empty, false will be returned. This API applies when the whole result set is obtained.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Type	Description
boolean	Returns true if the operation is successful; returns false otherwise.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  let moved: boolean;
  kvStore.getResultSet('batch_test_string_key').then((result) => {
    console.info('getResultSet succeed.');
    resultSet = result;
    do {
      moved = resultSet.moveToNext();
      const entry = resultSet.getEntry();
      console.info("moveToNext succeed: " + moved);
    } while (moved)
  }).catch((err: BusinessError) => {
    console.error('getResultSet failed: ' + err);
  });
} catch (e) {
  console.error("moveToNext failed: " + e);
}

moveToPrevious

moveToPrevious(): boolean

Moves the data read position to the previous row. If the result set is empty, false will be returned. This API applies when the whole result set is obtained.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Type	Description
boolean	Returns true if the operation is successful; returns false otherwise.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  let moved: boolean;
  kvStore.getResultSet('batch_test_string_key').then((result) => {
    console.info('getResultSet succeed.');
    resultSet = result;
    moved = resultSet.moveToLast();
    moved = resultSet.moveToPrevious();
    console.info("moveToPrevious succeed:" + moved);
  }).catch((err: BusinessError) => {
    console.error('getResultSet failed: ' + err);
  });
} catch (e) {
  console.error("moveToPrevious failed: " + e);
}

move

move(offset: number): boolean

Moves the data read position with the specified offset from the current position. That is, moves the number of rows specified by offset from the current position.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
offset	number	Yes	Offset to move the data read position. A negative value means to move backward, and a positive value means to move forward.

Return value

Type	Description
boolean	Returns true if the operation is successful; returns false otherwise.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  let moved: boolean;
  kvStore.getResultSet('batch_test_string_key').then((result) => {
    console.info('Succeeded in getting resultSet');
    resultSet = result;
    moved = resultSet.move(2); // If the current position is 0, move the read position forward by two rows, that is, move to row 3.
    console.info(`Succeeded in moving.moved = ${moved}`);
  }).catch((err: BusinessError) => {
    console.error(`Failed to get resultSet.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to move.code is ${error.code},message is ${error.message}`);
}

moveToPosition

moveToPosition(position: number): boolean

Moves the data read position from 0 to an absolute position.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
position	number	Yes	Absolute position to move to.

Return value

Type	Description
boolean	Returns true if the operation is successful; returns false otherwise.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  let moved: boolean;
  kvStore.getResultSet('batch_test_string_key').then((result) => {
    console.info('Succeeded in getting resultSet');
    resultSet = result;
    moved = resultSet.moveToPosition(1);
    console.info(`Succeeded in moving to position.moved=${moved}`);
  }).catch((err: BusinessError) => {
    console.error(`Failed to get resultSet.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to move to position.code is ${error.code},message is ${error.message}`);
}

isFirst

isFirst(): boolean

Checks whether the data read position is the first row.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Type	Description
boolean	Returns true if the first row is being read; returns false otherwise.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  let isfirst: boolean;
  kvStore.getResultSet('batch_test_string_key').then((result) => {
    console.info('getResultSet succeed.');
    resultSet = result;
    isfirst = resultSet.isFirst();
    console.info("Check isFirst succeed:" + isfirst);
  }).catch((err: BusinessError) => {
    console.error('getResultSet failed: ' + err);
  });
} catch (e) {
  console.error("Check isFirst failed: " + e);
}

isLast

isLast(): boolean

Checks whether the data read position is the last row.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Type	Description
boolean	Returns true if the last row is being read; returns false otherwise.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  let islast: boolean;
  kvStore.getResultSet('batch_test_string_key').then((result) => {
    console.info('getResultSet succeed.');
    resultSet = result;
    islast = resultSet.isLast();
    console.info("Check isLast succeed: " + islast);
  }).catch((err: BusinessError) => {
    console.error('getResultSet failed: ' + err);
  });
} catch (e) {
  console.error("Check isLast failed: " + e);
}

isBeforeFirst

isBeforeFirst(): boolean

Checks whether the data read position is before the first row.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Type	Description
boolean	Returns true if the data read position is before the first row; returns false otherwise.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  kvStore.getResultSet('batch_test_string_key').then((result) => {
    console.info('getResultSet succeed.');
    resultSet = result;
    const isbeforefirst = resultSet.isBeforeFirst();
    console.info("Check isBeforeFirst succeed: " + isbeforefirst);
  }).catch((err: BusinessError) => {
    console.error('getResultSet failed: ' + err);
  });
} catch (e) {
  console.error("Check isBeforeFirst failed: " + e);
}

isAfterLast

isAfterLast(): boolean

Checks whether the data read position is after the last row.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Type	Description
boolean	Returns true if the data read position is after the last row; returns false otherwise.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  kvStore.getResultSet('batch_test_string_key').then((result) => {
    console.info('getResultSet succeed.');
    resultSet = result;
    const isafterlast = resultSet.isAfterLast();
    console.info("Check isAfterLast succeed:" + isafterlast);
  }).catch((err: BusinessError) => {
    console.error('getResultSet failed: ' + err);
  });
} catch (e) {
  console.error("Check isAfterLast failed: " + e);
}

getEntry

getEntry(): Entry

Obtains the KV pair from the current position.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Type	Description
Entry	KV pair obtained.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  kvStore.getResultSet('batch_test_string_key').then((result) => {
    console.info('getResultSet succeed.');
    resultSet = result;
    const entry = resultSet.getEntry();
    console.info("getEntry succeed:" + JSON.stringify(entry));
  }).catch((err: BusinessError) => {
    console.error('getResultSet failed: ' + err);
  });
} catch (e) {
  console.error("getEntry failed: " + e);
}

Query

Provides methods to create a Query object, which defines different data query criteria. A Query object supports a maximum of 256 predicates.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

constructor

constructor()

A constructor used to create a Schema instance.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

reset

reset(): Query

Resets the Query object.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Type	Description
Query	Query object reset.

Example

import { BusinessError } from '@ohos.base';

try {
  let query: distributedKVStore.Query|null = new distributedKVStore.Query();
  query.equalTo("key", "value");
  console.info("query is " + query.getSqlLike());
  query.reset();
  console.info("query is " + query.getSqlLike());
  query = null;
} catch (e) {
  console.error("simply calls should be ok :" + e);
}

equalTo

equalTo(field: string, value: number|string|boolean): Query

Creates a Query object to match the specified field whose value is equal to the given value.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
fieId	string	Yes	Field to match. It cannot contain ‘^’.
value	number|string|boolean	Yes	Value specified.

Return value

Type	Description
Query	Query object created.

Example

import { BusinessError } from '@ohos.base';

try {
  let query: distributedKVStore.Query|null = new distributedKVStore.Query();
  query.equalTo("field", "value");
  console.info(`query is ${query.getSqlLike()}`);
  query = null;
} catch (e) {
  let error = e as BusinessError;
  console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}

notEqualTo

notEqualTo(field: string, value: number|string|boolean): Query

Creates a Query object to match the specified field whose value is not equal to the specified value.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
fieId	string	Yes	Field to match. It cannot contain ‘^’.
value	number|string|boolean	Yes	Value specified.

Return value

Type	Description
Query	Query object created.

Example

import { BusinessError } from '@ohos.base';

try {
  let query: distributedKVStore.Query|null = new distributedKVStore.Query();
  query.notEqualTo("field", "value");
  console.info(`query is ${query.getSqlLike()}`);
  query = null;
} catch (e) {
  let error = e as BusinessError;
  console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}

greaterThan

greaterThan(field: string, value: number|string|boolean): Query

Creates a Query object to match the specified field whose value is greater than the specified value.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters |Name|Type|Mandatory|Description | |—–|——|—-|———————–| |fieId|string|Yes |Field to match. It cannot contain ‘^’.| |value|number|string|boolean|Yes |Value specified.|

Return value

Type	Description
Query	Query object created.

Example

import { BusinessError } from '@ohos.base';

try {
    let query: distributedKVStore.Query|null = new distributedKVStore.Query();
    query.greaterThan("field", "value");
    console.info(`query is ${query.getSqlLike()}`);
    query = null;
} catch (e) {
    let error = e as BusinessError;
    console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}

lessThan

lessThan(field: string, value: number|string): Query

Creates a Query object to match the specified field whose value is less than the specified value.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
fieId	string	Yes	Field to match. It cannot contain ‘^’.
value	number|string	Yes	Value specified.

Return value

Type	Description
Query	Query object created.

Example

import { BusinessError } from '@ohos.base';

try {
    let query: distributedKVStore.Query|null = new distributedKVStore.Query();
    query.lessThan("field", "value");
    console.info(`query is ${query.getSqlLike()}`);
    query = null;
} catch (e) {
    let error = e as BusinessError;
    console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}

greaterThanOrEqualTo

greaterThanOrEqualTo(field: string, value: number|string): Query

Creates a Query object to match the specified field whose value is greater than or equal to the specified value.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
fieId	string	Yes	Field to match. It cannot contain ‘^’.
value	number|string	Yes	Value specified.

Return value

Type	Description
Query	Query object created.

Example

import { BusinessError } from '@ohos.base';

try {
    let query: distributedKVStore.Query|null = new distributedKVStore.Query();
    query.greaterThanOrEqualTo("field", "value");
    console.info(`query is ${query.getSqlLike()}`);
    query = null;
} catch (e) {
    let error = e as BusinessError;
    console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}

lessThanOrEqualTo

lessThanOrEqualTo(field: string, value: number|string): Query

Creates a Query object to match the specified field whose value is less than or equal to the specified value.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
fieId	string	Yes	Field to match. It cannot contain ‘^’.
value	number|string	Yes	Value specified.

Return value

Type	Description
Query	Query object created.

Example

import { BusinessError } from '@ohos.base';

try {
    let query: distributedKVStore.Query|null = new distributedKVStore.Query();
    query.lessThanOrEqualTo("field", "value");
    console.info(`query is ${query.getSqlLike()}`);
    query = null;
} catch (e) {
    let error = e as BusinessError;
    console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}

isNull

isNull(field: string): Query

Creates a Query object to match the specified field whose value is null.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
fieId	string	Yes	Field to match. It cannot contain ‘^’.

Return value

Type	Description
Query	Query object created.

Example

import { BusinessError } from '@ohos.base';

try {
    let query: distributedKVStore.Query|null = new distributedKVStore.Query();
    query.isNull("field");
    console.info(`query is ${query.getSqlLike()}`);
    query = null;
} catch (e) {
    let error = e as BusinessError;
    console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}

inNumber

inNumber(field: string, valueList: number[]): Query

Creates a Query object to match the specified field whose value is within the specified list of numbers.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
fieId	string	Yes	Field to match. It cannot contain ‘^’.
valueList	number[]	Yes	List of numbers.

Return value

Type	Description
Query	Query object created.

Example

import { BusinessError } from '@ohos.base';

try {
    let query: distributedKVStore.Query|null = new distributedKVStore.Query();
    query.inNumber("field", [0, 1]);
    console.info(`query is ${query.getSqlLike()}`);
    query = null;
} catch (e) {
    let error = e as BusinessError;
    console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}

inString

inString(field: string, valueList: string[]): Query

Creates a Query object to match the specified field whose value is within the specified list of strings.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
fieId	string	Yes	Field to match. It cannot contain ‘^’.
valueList	string[]	Yes	List of strings.

Return value

Type	Description
Query	Query object created.

Example

import { BusinessError } from '@ohos.base';

try {
    let query: distributedKVStore.Query|null = new distributedKVStore.Query();
    query.inString("field", ['test1', 'test2']);
    console.info(`query is ${query.getSqlLike()}`);
    query = null;
} catch (e) {
    let error = e as BusinessError;
    console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}

notInNumber

notInNumber(field: string, valueList: number[]): Query

Creates a Query object to match the specified field whose value is not within the specified list of numbers.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
fieId	string	Yes	Field to match. It cannot contain ‘^’.
valueList	number[]	Yes	List of numbers.

Return value

Type	Description
Query	Query object created.

Example

import { BusinessError } from '@ohos.base';

try {
    let query: distributedKVStore.Query|null = new distributedKVStore.Query();
    query.notInNumber("field", [0, 1]);
    console.info(`query is ${query.getSqlLike()}`);
    query = null;
} catch (e) {
    let error = e as BusinessError;
    console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}

notInString

notInString(field: string, valueList: string[]): Query

Creates a Query object to match the specified field whose value is not within the specified list of strings.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
fieId	string	Yes	Field to match. It cannot contain ‘^’.
valueList	string[]	Yes	List of strings.

Return value

Type	Description
Query	Query object created.

Example

import { BusinessError } from '@ohos.base';

try {
    let query: distributedKVStore.Query|null = new distributedKVStore.Query();
    query.notInString("field", ['test1', 'test2']);
    console.info(`query is ${query.getSqlLike()}`);
    query = null;
} catch (e) {
    let error = e as BusinessError;
    console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}

like

like(field: string, value: string): Query

Creates a Query object to match the specified field whose value is similar to the specified string.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
fieId	string	Yes	Field to match. It cannot contain ‘^’.
value	string	Yes	String specified.

Return value

Type	Description
Query	Query object created.

Example

import { BusinessError } from '@ohos.base';

try {
    let query: distributedKVStore.Query|null = new distributedKVStore.Query();
    query.like("field", "value");
    console.info(`query is ${query.getSqlLike()}`);
    query = null;
} catch (e) {
    let error = e as BusinessError;
    console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}

unlike

unlike(field: string, value: string): Query

Creates a Query object to match the specified field whose value is not similar to the specified string.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
fieId	string	Yes	Field to match. It cannot contain ‘^’.
value	string	Yes	String specified.

Return value

Type	Description
Query	Query object created.

Example

import { BusinessError } from '@ohos.base';

try {
    let query: distributedKVStore.Query|null = new distributedKVStore.Query();
    query.unlike("field", "value");
    console.info(`query is ${query.getSqlLike()}`);
    query = null;
} catch (e) {
    let error = e as BusinessError;
    console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}

and

and(): Query

Creates a Query object with the AND condition.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Type	Description
Query	Query object created.

Example

import { BusinessError } from '@ohos.base';

try {
    let query: distributedKVStore.Query|null = new distributedKVStore.Query();
    query.notEqualTo("field", "value1");
    query.and();
    query.notEqualTo("field", "value2");
    console.info("query is " + query.getSqlLike());
    query = null;
} catch (e) {
    console.error("duplicated calls should be ok :" + e);
}

or

or(): Query

Creates a Query object with the OR condition.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Type	Description
Query	Query object created.

Example

import { BusinessError } from '@ohos.base';

try {
    let query: distributedKVStore.Query|null = new distributedKVStore.Query();
    query.notEqualTo("field", "value1");
    query.or();
    query.notEqualTo("field", "value2");
    console.info("query is " + query.getSqlLike());
    query = null;
} catch (e) {
    console.error("duplicated calls should be ok :" + e);
}

orderByAsc

orderByAsc(field: string): Query

Creates a Query object to sort the query results in ascending order.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
fieId	string	Yes	Field to match. It cannot contain ‘^’.

Return value

Type	Description
Query	Query object created.

Example

import { BusinessError } from '@ohos.base';

try {
    let query: distributedKVStore.Query|null = new distributedKVStore.Query();
    query.notEqualTo("field", "value");
    query.orderByAsc("field");
    console.info(`query is ${query.getSqlLike()}`);
    query = null;
} catch (e) {
    let error = e as BusinessError;
    console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}

orderByDesc

orderByDesc(field: string): Query

Creates a Query object to sort the query results in descending order.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
fieId	string	Yes	Field to match. It cannot contain ‘^’.

Return value

Type	Description
Query	Query object created.

Example

import { BusinessError } from '@ohos.base';

try {
    let query: distributedKVStore.Query|null = new distributedKVStore.Query();
    query.notEqualTo("field", "value");
    query.orderByDesc("field");
    console.info(`query is ${query.getSqlLike()}`);
    query = null;
} catch (e) {
    let error = e as BusinessError;
    console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}

limit

limit(total: number, offset: number): Query

Creates a Query object to specify the number of records of the query result and where to start. This API must be called after the invocation of the orderByAsc(), orderByDesc(), and the query APIs of the Query object.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
total	number	Yes	Number of results to query.
offset	number	Yes	Start position for query.

Return value

Type	Description
Query	Query object created.

Example

import { BusinessError } from '@ohos.base';

let total = 10;
let offset = 1;
try {
  let query: distributedKVStore.Query|null = new distributedKVStore.Query();
  query.notEqualTo("field", "value");
  query.limit(total, offset);
  console.info(`query is ${query.getSqlLike()}`);
  query = null;
} catch (e) {
  let error = e as BusinessError;
  console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}

isNotNull

isNotNull(field: string): Query

Creates a Query object to match the specified field whose value is not null.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
fieId	string	Yes	Field to match. It cannot contain ‘^’.

Return value

Type	Description
Query	Query object created.

Example

import { BusinessError } from '@ohos.base';

try {
  let query: distributedKVStore.Query|null = new distributedKVStore.Query();
  query.isNotNull("field");
  console.info(`query is ${query.getSqlLike()}`);
  query = null;
} catch (e) {
  let error = e as BusinessError;
  console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}

beginGroup

beginGroup(): Query

Creates a Query object for a query condition group with a left parenthesis.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Type	Description
Query	Query object created.

Example

import { BusinessError } from '@ohos.base';

try {
    let query: distributedKVStore.Query|null = new distributedKVStore.Query();
    query.beginGroup();
    query.isNotNull("field");
    query.endGroup();
    console.info("query is " + query.getSqlLike());
    query = null;
} catch (e) {
    console.error("duplicated calls should be ok :" + e);
}

endGroup

endGroup(): Query

Creates a Query object for a query condition group with a right parenthesis.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Type	Description
Query	Query object created.

Example

import { BusinessError } from '@ohos.base';

try {
    let query: distributedKVStore.Query|null = new distributedKVStore.Query();
    query.beginGroup();
    query.isNotNull("field");
    query.endGroup();
    console.info("query is " + query.getSqlLike());
    query = null;
} catch (e) {
    console.error("duplicated calls should be ok :" + e);
}

prefixKey

prefixKey(prefix: string): Query

Creates a Query object with a specified key prefix.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
prefix	string	Yes	Key prefix.

Return value

Type	Description
Query	Query object created.

Example

import { BusinessError } from '@ohos.base';

try {
    let query: distributedKVStore.Query|null = new distributedKVStore.Query();
    query.prefixKey("$.name");
    query.prefixKey("0");
    console.info(`query is ${query.getSqlLike()}`);
    query = null;
} catch (e) {
    let error = e as BusinessError;
    console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}

setSuggestIndex

setSuggestIndex(index: string): Query

Creates a Query object with an index preferentially used for query.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
index	string	Yes	Index preferentially used for query.

Return value

Type	Description
Query	Query object created.

Example

import { BusinessError } from '@ohos.base';

try {
    let query: distributedKVStore.Query|null = new distributedKVStore.Query();
    query.setSuggestIndex("$.name");
    query.setSuggestIndex("0");
    console.info(`query is ${query.getSqlLike()}`);
    query = null;
} catch (e) {
    let error = e as BusinessError;
    console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}

deviceId

deviceId(deviceId:string):Query

Creates a Query object with the device ID as the key prefix. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
deviceId	string	Yes	Device ID.

Return value

Type	Description
Query	Query object created.

Example

import { BusinessError } from '@ohos.base';

try {
    let query: distributedKVStore.Query|null = new distributedKVStore.Query();
    query.deviceId("deviceId");
    console.info(`query is ${query.getSqlLike()}`);
} catch (e) {
    let error = e as BusinessError;
    console.error(`duplicated calls should be ok.code is ${error.code},message is ${error.message}`);
}

getSqlLike

getSqlLike():string

Obtains the query statement of the Query object.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Type	Description
string	Returns the query statement obtained.

Example

import { BusinessError } from '@ohos.base';

try {
    let query: distributedKVStore.Query|null = new distributedKVStore.Query();
    let sql1 = query.getSqlLike();
    console.info(`GetSqlLike sql= ${sql1}`);
} catch (e) {
    console.error("duplicated calls should be ok : " + e);
}

SingleKVStore

Implements data management in a single KV store, such as adding data, deleting data, and subscribing to data changes or data synchronization completion.

Before calling any method in SingleKVStore, you must use getKVStore to obtain a SingleKVStore instance.

put

put(key: string, value: Uint8Array|string|number|boolean, callback: AsyncCallback<void>): void

Adds a KV pair of the specified type to this KV store. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
key	string	Yes	Key of the KV pair to add. It cannot be empty, and the length cannot exceed MAX_KEY_LENGTH.
value	Uint8Array |string |number |boolean	Yes	Value of the KV pair to add. The value type can be Uint8Array, number, string, or boolean. A value of the Uint8Array or string type cannot exceed MAX_VALUE_LENGTH.
callback	AsyncCallback<void>	Yes	Callback invoked to return the result.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

For details about the error codes, see RDB Error Codes.

ID	Error Message
14800047	The WAL file size exceeds the default limit.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;
const KEY_TEST_STRING_ELEMENT = 'key_test_string';
const VALUE_TEST_STRING_ELEMENT = 'value-test-string';
try {
  kvStore.put(KEY_TEST_STRING_ELEMENT, VALUE_TEST_STRING_ELEMENT, (err) => {
    if (err != undefined) {
      console.error(`Failed to put.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info("Succeeded in putting");
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

put

put(key: string, value: Uint8Array|string|number|boolean): Promise<void>

Adds a KV pair of the specified type to this KV store. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
key	string	Yes	Key of the KV pair to add. It cannot be empty, and the length cannot exceed MAX_KEY_LENGTH.
value	Uint8Array |string |number |boolean	Yes	Value of the KV pair to add. The value type can be Uint8Array, number, string, or boolean. A value of the Uint8Array or string type cannot exceed MAX_VALUE_LENGTH.

Return value

Type	Description
Promise<void>	Promise that returns no value.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

For details about the error codes, see RDB Error Codes.

ID	Error Message
14800047	The WAL file size exceeds the default limit.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;
const KEY_TEST_STRING_ELEMENT = 'key_test_string';
const VALUE_TEST_STRING_ELEMENT = 'value-test-string';
try {
  kvStore.put(KEY_TEST_STRING_ELEMENT, VALUE_TEST_STRING_ELEMENT).then(() => {
    console.info(`Succeeded in putting data`);
  }).catch((err: BusinessError) => {
    console.error(`Failed to put.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

putBatch

putBatch(entries: Entry[], callback: AsyncCallback<void>): void

Batch inserts KV pairs to this single KV store. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
entries	Entry[]	Yes	KV pairs to insert in batches. An entries object allows a maximum of 128 entries.
callback	AsyncCallback<void>	Yes	Callback invoked to return the result.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

For details about the error codes, see RDB Error Codes.

ID	Error Message
14800047	The WAL file size exceeds the default limit.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_string_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.STRING,
        value: 'batch_test_string_value'
      }
    }
    entries.push(entry);
  }
  console.info(`entries: ${entries}`);
  kvStore.putBatch(entries, async (err) => {
    if (err != undefined) {
      console.error(`Failed to put Batch.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in putting Batch');
    kvStore.getEntries('batch_test_string_key', (err, entries) => {
      if (err != undefined) {
        console.error(`Failed to get Entries.code is ${err.code},message is ${err.message}`);
      }
      console.info('Succeeded in getting Entries');
      console.info(`entries.length: ${entries.length}`);
      console.info(`entries[0]: ${entries[0]}`);
    });
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message} `);
}

putBatch

putBatch(entries: Entry[]): Promise<void>

Batch inserts KV pairs to this single KV store. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
entries	Entry[]	Yes	KV pairs to insert in batches. An entries object allows a maximum of 128 entries.

Return value

Type	Description
Promise<void>	Promise that returns no value.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

For details about the error codes, see RDB Error Codes.

ID	Error Message
14800047	The WAL file size exceeds the default limit.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_string_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.STRING,
        value: 'batch_test_string_value'
      }
    }
    entries.push(entry);
  }
  console.info(`entries: ${entries}`);
  kvStore.putBatch(entries).then(async () => {
    console.info('Succeeded in putting Batch');
    kvStore.getEntries('batch_test_string_key').then((entries) => {
      console.info('Succeeded in getting Entries');
      console.info(`PutBatch ${entries}`);
    }).catch((err: BusinessError) => {
      console.error(`Failed to get Entries.code is ${err.code},message is ${err.message}`);
    });
  }).catch((err: BusinessError) => {
    console.error(`Failed to put Batch.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message} `);
}

putBatch

putBatch(value: Array<ValuesBucket>, callback: AsyncCallback<void>): void

Writes data to this single KV store. This API uses an asynchronous callback to return the result.

Model restriction: This API can be used only in the stage model.

System API: This is a system API.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
value	Array<ValuesBucket>	Yes	Data to write.
callback	AsyncCallback<void>	Yes	Callback invoked to return the result.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

For details about the error codes, see RDB Error Codes.

ID	Error Message
14800047	The WAL file size exceeds the default limit.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  let v8Arr: distributedKVStore.Entry[] = [];
  let arr = new Uint8Array([4, 5, 6, 7]);
  let vb1: distributedKVStore.Entry = { key: "name_1", value: 32 }
  let vb2: distributedKVStore.Entry = { key: "name_2", value: arr };
  let vb3: distributedKVStore.Entry = { key: "name_3", value: "lisi" };

  v8Arr.push(vb1);
  v8Arr.push(vb2);
  v8Arr.push(vb3);
  kvStore.putBatch(v8Arr, async (err) => {
    if (err != undefined) {
      console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in putting batch');
  })
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to put batch.code is ${error.code},message is ${error.message}`);
}

putBatch

putBatch(value: Array<ValuesBucket>): Promise<void>

Write data to this KV store. This API uses a promise to return the result.

Model restriction: This API can be used only in the stage model.

System API: This is a system API.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
value	Array<ValuesBucket>	Yes	Data to write.

Return value

Type	Description
Promise<void>	Promise that returns no value.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

For details about the error codes, see RDB Error Codes.

ID	Error Message
14800047	The WAL file size exceeds the default limit.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  let v8Arr: distributedKVStore.Entry[] = [];
  let arr = new Uint8Array([4, 5, 6, 7]);
  let vb1: distributedKVStore.Entry = { key: "name_1", value: 32 }
  let vb2: distributedKVStore.Entry = { key: "name_2", value: arr };
  let vb3: distributedKVStore.Entry = { key: "name_3", value: "lisi" };

  v8Arr.push(vb1);
  v8Arr.push(vb2);
  v8Arr.push(vb3);
  kvStore.putBatch(v8Arr).then(async () => {
    console.info(`Succeeded in putting patch`);
  }).catch((err: BusinessError) => {
    console.error(`putBatch fail.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`putBatch fail.code is ${error.code},message is ${error.message}`);
}

delete

delete(key: string, callback: AsyncCallback<void>): void

Deletes a KV pair from this KV store. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
key	string	Yes	Key of the KV pair to delete. It cannot be empty, and the length cannot exceed MAX_KEY_LENGTH.
callback	AsyncCallback<void>	Yes	Callback invoked to return the result.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

For details about the error codes, see RDB Error Codes.

ID	Error Message
14800047	The WAL file size exceeds the default limit.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

const KEY_TEST_STRING_ELEMENT = 'key_test_string';
const VALUE_TEST_STRING_ELEMENT = 'value-test-string';
try {
  kvStore.put(KEY_TEST_STRING_ELEMENT, VALUE_TEST_STRING_ELEMENT, (err) => {
    if (err != undefined) {
      console.error(`Failed to put.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in putting');
    kvStore.delete(KEY_TEST_STRING_ELEMENT, (err) => {
      if (err != undefined) {
        console.error(`Failed to delete.code is ${err.code},message is ${err.message}`);
        return;
      }
      console.info('Succeeded in deleting');
    });
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

delete

delete(key: string): Promise<void>

Deletes a KV pair from this KV store. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
key	string	Yes	Key of the KV pair to delete. It cannot be empty, and the length cannot exceed MAX_KEY_LENGTH.

Return value

Type	Description
Promise<void>	Promise that returns no value.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

For details about the error codes, see RDB Error Codes.

ID	Error Message
14800047	The WAL file size exceeds the default limit.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

const KEY_TEST_STRING_ELEMENT = 'key_test_string';
const VALUE_TEST_STRING_ELEMENT = 'value-test-string';
try {
  kvStore.put(KEY_TEST_STRING_ELEMENT, VALUE_TEST_STRING_ELEMENT).then(() => {
    console.info(`Succeeded in putting data`);
    kvStore.delete(KEY_TEST_STRING_ELEMENT).then(() => {
      console.info('Succeeded in deleting');
    }).catch((err: BusinessError) => {
      console.error(`Failed to delete.code is ${err.code},message is ${err.message}`);
    });
  }).catch((err: BusinessError) => {
    console.error(`Failed to put.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

delete

delete(predicates: dataSharePredicates.DataSharePredicates, callback: AsyncCallback<void>)

Deletes KV pairs from this KV store. This API uses an asynchronous callback to return the result.

Model restriction: This API can be used only in the stage model.

System API: This is a system API.

System capability: SystemCapability.DistributedDataManager.DataShare.Provider

Parameters

Name	Type	Mandatory	Description
predicates	dataSharePredicates.DataSharePredicates	Yes	DataSharePredicates object that specifies the KV pairs to delete. If this parameter is null, define the processing logic.
callback	AsyncCallback<void>	Yes	Callback invoked to return the result.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

For details about the error codes, see RDB Error Codes.

ID	Error Message
14800047	The WAL file size exceeds the default limit.

Example

import dataSharePredicates from '@ohos.data.dataSharePredicates';
import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
  let predicates = new dataSharePredicates.DataSharePredicates();
  let arr = ["name"];
  predicates.inKeys(arr);
  kvStore.put("name", "bob", (err) => {
    if (err != undefined) {
      console.error(`Failed to put.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info("Succeeded in putting");
    kvStore.delete(predicates, (err) => {
      if (err == undefined) {
        console.info('Succeeded in deleting');
      } else {
        console.error(`Failed to delete.code is ${err.code},message is ${err.message}`);
      }
    });
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

delete

delete(predicates: dataSharePredicates.DataSharePredicates): Promise<void>

Deletes KV pairs from this KV store. This API uses a promise to return the result.

Model restriction: This API can be used only in the stage model.

System API: This is a system API.

System capability: SystemCapability.DistributedDataManager.DataShare.Provider

Parameters

Name	Type	Mandatory	Description
predicates	dataSharePredicates.DataSharePredicates	Yes	DataSharePredicates object that specifies the KV pairs to delete. If this parameter is null, define the processing logic.

Return value

Type	Description
Promise<void>	Promise that returns no value.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

For details about the error codes, see RDB Error Codes.

ID	Error Message
14800047	The WAL file size exceeds the default limit.

Example

import dataSharePredicates from '@ohos.data.dataSharePredicates';
import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
  let predicates = new dataSharePredicates.DataSharePredicates();
  let arr = ["name"];
  predicates.inKeys(arr);
  kvStore.put("name", "bob").then(() => {
    console.info(`Succeeded in putting data`);
    kvStore.delete(predicates).then(() => {
      console.info('Succeeded in deleting');
    }).catch((err: BusinessError) => {
      console.error(`Failed to delete.code is ${err.code},message is ${err.message}`);
    });
  }).catch((err: BusinessError) => {
    console.error(`Failed to put.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

deleteBatch

deleteBatch(keys: string[], callback: AsyncCallback<void>): void

Batch deletes KV pairs from this single KV store. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
keys	string[]	Yes	KV pairs to delete in batches.
callback	AsyncCallback<void>	Yes	Callback invoked to return the result.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

For details about the error codes, see RDB Error Codes.

ID	Error Message
14800047	The WAL file size exceeds the default limit.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
  let entries: distributedKVStore.Entry[] = [];
  let keys: string[] = [];
  for (let i = 0; i < 5; i++) {
    let key = 'batch_test_string_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.STRING,
        value: 'batch_test_string_value'
      }
    }
    entries.push(entry);
    keys.push(key + i);
  }
  console.info(`entries: ${entries}`);
  kvStore.putBatch(entries, async (err) => {
    if (err != undefined) {
      console.error(`Failed to put Batch.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in putting Batch');
    kvStore.deleteBatch(keys, async (err) => {
      if (err != undefined) {
        console.error(`Failed to delete Batch.code is ${err.code},message is ${err.message}`);
        return;
      }
      console.info('Succeeded in deleting Batch');
    });
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

deleteBatch

deleteBatch(keys: string[]): Promise<void>

Batch deletes KV pairs from this single KV store. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
keys	string[]	Yes	KV pairs to delete in batches.

Return value

Type	Description
Promise<void>	Promise that returns no value.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

For details about the error codes, see RDB Error Codes.

ID	Error Message
14800047	The WAL file size exceeds the default limit.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;
try {
  let entries: distributedKVStore.Entry[] = [];
  let keys: string[] = [];
  for (let i = 0; i < 5; i++) {
    let key = 'batch_test_string_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.STRING,
        value: 'batch_test_string_value'
      }
    }
    entries.push(entry);
    keys.push(key + i);
  }
  console.info(`entries: ${entries}`);
  kvStore.putBatch(entries).then(async () => {
    console.info('Succeeded in putting Batch');
    kvStore.deleteBatch(keys).then(() => {
      console.info('Succeeded in deleting Batch');
    }).catch((err: BusinessError) => {
      console.error(`Failed to delete Batch.code is ${err.code},message is ${err.message}`);
    });
  }).catch((err: BusinessError) => {
    console.error(`Failed to put Batch.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

removeDeviceData

removeDeviceData(deviceId: string, callback: AsyncCallback<void>): void

Deletes data of a device. This API uses an asynchronous callback to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Name	Type	Mandatory	Description
deviceId	string	Yes	ID of the target device.
callback	AsyncCallback<void>	Yes	Callback invoked to return the result.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;
const KEY_TEST_STRING_ELEMENT = 'key_test_string_2';
const VALUE_TEST_STRING_ELEMENT = 'value-string-002';
try {
  kvStore.put(KEY_TEST_STRING_ELEMENT, VALUE_TEST_STRING_ELEMENT, async (err) => {
    console.info('Succeeded in putting data');
    const deviceid = 'no_exist_device_id';
    kvStore.removeDeviceData(deviceid, async (err) => {
      if (err == undefined) {
        console.info('succeeded in removing device data');
      } else {
        console.error(`Failed to remove device data.code is ${err.code},message is ${err.message} `);
        kvStore.get(KEY_TEST_STRING_ELEMENT, async (err, data) => {
          console.info('Succeeded in getting data');
        });
      }
    });
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`)
}

removeDeviceData

removeDeviceData(deviceId: string): Promise<void>

Deletes data of a device. This API uses a promise to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Name	Type	Mandatory	Description
deviceId	string	Yes	ID of the target device.

Return value

Type	Description
Promise<void>	Promise that returns no value.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;
const KEY_TEST_STRING_ELEMENT = 'key_test_string_2';
const VALUE_TEST_STRING_ELEMENT = 'value-string-001';
try {
  kvStore.put(KEY_TEST_STRING_ELEMENT, VALUE_TEST_STRING_ELEMENT).then(() => {
    console.info('Succeeded in putting data');
  }).catch((err: BusinessError) => {
    console.error(`Failed to put data.code is ${err.code},message is ${err.message} `);
  });
  const deviceid = 'no_exist_device_id';
  kvStore.removeDeviceData(deviceid).then(() => {
    console.info('succeeded in removing device data');
  }).catch((err: BusinessError) => {
    console.error(`Failed to remove device data.code is ${err.code},message is ${err.message} `);
  });
  kvStore.get(KEY_TEST_STRING_ELEMENT).then((data) => {
    console.info('Succeeded in getting data');
  }).catch((err: BusinessError) => {
    console.error(`Failed to get data.code is ${err.code},message is ${err.message} `);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`)
}

get

get(key: string, callback: AsyncCallback<boolean|string|number|Uint8Array>): void

Obtains the value of the specified key. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
key	string	Yes	Key of the value to obtain. It cannot be empty, and the length cannot exceed MAX_KEY_LENGTH.
callback	AsyncCallback<boolean |string |number |Uint8Array>	Yes	Callback invoked to return the value obtained.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100004	Not found.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

const KEY_TEST_STRING_ELEMENT = 'key_test_string';
const VALUE_TEST_STRING_ELEMENT = 'value-test-string';
try {
  kvStore.put(KEY_TEST_STRING_ELEMENT, VALUE_TEST_STRING_ELEMENT, (err) => {
    if (err != undefined) {
      console.error(`Failed to put.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info("Succeeded in putting");
    kvStore.get(KEY_TEST_STRING_ELEMENT, (err, data) => {
      if (err != undefined) {
        console.error(`Failed to get.code is ${err.code},message is ${err.message}`);
        return;
      }
      console.info(`Succeeded in getting data.data=${data}`);
    });
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to get.code is ${error.code},message is ${error.message}`);
}

get

get(key: string): Promise<boolean|string|number|Uint8Array>

Obtains the value of the specified key. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
key	string	Yes	Key of the value to obtain. It cannot be empty, and the length cannot exceed MAX_KEY_LENGTH.

Return value

Type	Description
Promise<Uint8Array |string |boolean |number>	Promise used to return the value obtained.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100004	Not found.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

const KEY_TEST_STRING_ELEMENT = 'key_test_string';
const VALUE_TEST_STRING_ELEMENT = 'value-test-string';
try {
  kvStore.put(KEY_TEST_STRING_ELEMENT, VALUE_TEST_STRING_ELEMENT).then(() => {
    console.info(`Succeeded in putting data`);
    kvStore.get(KEY_TEST_STRING_ELEMENT).then((data) => {
      console.info(`Succeeded in getting data.data=${data}`);
    }).catch((err: BusinessError) => {
      console.error(`Failed to get.code is ${err.code},message is ${err.message}`);
    });
  }).catch((err: BusinessError) => {
    console.error(`Failed to put.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to get.code is ${error.code},message is ${error.message}`);
}

getEntries

getEntries(keyPrefix: string, callback: AsyncCallback<Entry[]>): void

Obtains all KV pairs that match the specified key prefix. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
keyPrefix	string	Yes	Key prefix to match.
callback	AsyncCallback<Entry[]>	Yes	Callback invoked to return the KV pairs that match the specified prefix.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_string_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.STRING,
        value: 'batch_test_string_value'
      }
    }
    entries.push(entry);
  }
  console.info(`entries: ${entries}`);
  kvStore.putBatch(entries, async (err) => {
    if (err != undefined) {
      console.error(`Failed to put Batch.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in putting Batch');
    kvStore.getEntries('batch_test_string_key', (err, entries) => {
      if (err != undefined) {
        console.error(`Failed to get Entries.code is ${err.code},message is ${err.message}`);
        return;
      }
      console.info('Succeeded in getting Entries');
      console.info(`entries.length: ${entries.length}`);
      console.info(`entries[0]: ${entries[0]}`);
    });
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message} `);
}

getEntries

getEntries(keyPrefix: string): Promise<Entry[]>

Obtains all KV pairs that match the specified key prefix. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
keyPrefix	string	Yes	Key prefix to match.

Return value

Type	Description
Promise<Entry[]>	Promise used to return the KV pairs that match the specified prefix.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_string_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.STRING,
        value: 'batch_test_string_value'
      }
    }
    entries.push(entry);
  }
  console.info(`entries: ${entries}`);
  kvStore.putBatch(entries).then(async () => {
    console.info('Succeeded in putting Batch');
    kvStore.getEntries('batch_test_string_key').then((entries) => {
      console.info('Succeeded in getting Entries');
      console.info(`PutBatch ${entries}`);
    }).catch((err: BusinessError) => {
      console.error(`Failed to get Entries.code is ${err.code},message is ${err.message}`);
    });
  }).catch((err: BusinessError) => {
    console.error(`Failed to put Batch.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message} `);
}

getEntries

getEntries(query: Query, callback: AsyncCallback<Entry[]>): void

Obtains the KV pairs that match the specified Query object. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
query	Query	Yes	Key prefix to match.
callback	AsyncCallback<Entry[]>	Yes	Callback invoked to return the KV pairs that match the specified Query object.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  let arr = new Uint8Array([21, 31]);
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_bool_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.BYTE_ARRAY,
        value: arr
      }
    }
    entries.push(entry);
  }
  console.info(`entries: {entries}`);
  kvStore.putBatch(entries, async (err) => {
    console.info('Succeeded in putting Batch');
    const query = new distributedKVStore.Query();
    query.prefixKey("batch_test");
    kvStore.getEntries(query, (err, entries) => {
      if (err != undefined) {
        console.error(`Failed to get Entries.code is ${err.code},message is ${err.message}`);
        return;
      }
      console.info('Succeeded in getting Entries');
      console.info(`entries.length: ${entries.length}`);
      console.info(`entries[0]: ${entries[0]}`);
    });
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to get Entries.code is ${error.code},message is ${error.message}`);
}

getEntries

getEntries(query: Query): Promise<Entry[]>

Obtains the KV pairs that match the specified Query object. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
query	Query	Yes	Query object to match.

Return value

Type	Description
Promise<Entry[]>	Promise used to return the KV pairs that match the specified Query object.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  let arr = new Uint8Array([21, 31]);
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_bool_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.BYTE_ARRAY,
        value: arr
      }
    }
    entries.push(entry);
  }
  console.info(`entries: {entries}`);
  kvStore.putBatch(entries).then(async () => {
    console.info('Succeeded in putting Batch');
    const query = new distributedKVStore.Query();
    query.prefixKey("batch_test");
    kvStore.getEntries(query).then((entries) => {
      console.info('Succeeded in getting Entries');
    }).catch((err: BusinessError) => {
      console.error(`Failed to get Entries.code is ${err.code},message is ${err.message}`);
    });
  }).catch((err: BusinessError) => {
    console.error(`Failed to get Entries.code is ${err.code},message is ${err.message}`)
  });
  console.info('Succeeded in getting Entries');
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to get Entries.code is ${error.code},message is ${error.message}`);
}

getResultSet

getResultSet(keyPrefix: string, callback: AsyncCallback<KVStoreResultSet>): void

Obtains a result set with the specified prefix from this single KV store. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
keyPrefix	string	Yes	Key prefix to match.
callback	AsyncCallback<KVStoreResultSet>	Yes	Callback invoked to return the result set with the specified prefix.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100001	Over max limits.
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  let resultSet: distributedKVStore.KVStoreResultSet = xxx;
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_string_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.STRING,
        value: 'batch_test_string_value'
      }
    }
    entries.push(entry);
  }
  kvStore.putBatch(entries, async (err) => {
    if (err != undefined) {
      console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in putting batch');
    kvStore.getResultSet('batch_test_string_key', async (err, result) => {
      if (err != undefined) {
        console.error(`Failed to get resultset.code is ${err.code},message is ${err.message}`);
        return;
      }
      console.info('Succeeded in getting result set');
      resultSet = result;
      kvStore.closeResultSet(resultSet, (err) => {
        if (err != undefined) {
          console.error(`Failed to close resultset.code is ${err.code},message is ${err.message}`);
          return;
        }
        console.info('Succeeded in closing result set');
      })
    });
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
} 

getResultSet

getResultSet(keyPrefix: string): Promise<KVStoreResultSet>

Obtains a result set with the specified prefix from this single KV store. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
keyPrefix	string	Yes	Key prefix to match.

Return value

Type	Description
Promise<KVStoreResultSet>	Promise used to return the result set with the specified prefix.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100001	Over max limits.
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  let resultSet: distributedKVStore.KVStoreResultSet = xxx;
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_string_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.STRING,
        value: 'batch_test_string_value'
      }
    }
    entries.push(entry);
  }
  kvStore.putBatch(entries).then(async () => {
    console.info('Succeeded in putting batch');
  }).catch((err: BusinessError) => {
    console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
  });
  kvStore.getResultSet('batch_test_string_key').then((result) => {
    console.info('Succeeded in getting result set');
    resultSet = result;
  }).catch((err: BusinessError) => {
    console.error(`Failed to get resultset.code is ${err.code},message is ${err.message}`);
  });
  kvStore.closeResultSet(resultSet).then(() => {
    console.info('Succeeded in closing result set');
  }).catch((err: BusinessError) => {
    console.error(`Failed to close resultset.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}

getResultSet

getResultSet(query: Query, callback: AsyncCallback<KVStoreResultSet>): void

Obtains a KVStoreResultSet object that matches the specified Query object. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
query	Query	Yes	Query object to match.
callback	AsyncCallback<KVStoreResultSet>	Yes	Callback invoked to return the KVStoreResultSet object obtained.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100001	Over max limits.
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  let resultSet: distributedKVStore.KVStoreResultSet = xxx;
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_string_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.STRING,
        value: 'batch_test_string_value'
      }
    }
    entries.push(entry);
  }
  kvStore.putBatch(entries, async (err) => {
    if (err != undefined) {
      console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in putting batch');
    const query = new distributedKVStore.Query();
    query.prefixKey("batch_test");
    kvStore.getResultSet(query, async (err, result) => {
      if (err != undefined) {
        console.error(`Failed to get resultset.code is ${err.code},message is ${err.message}`);
        return;
      }
      console.info('Succeeded in getting result set');
    });
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

getResultSet

getResultSet(query: Query): Promise<KVStoreResultSet>

Obtains a KVStoreResultSet object that matches the specified Query object. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
query	Query	Yes	Query object to match.

Return value

Type	Description
Promise<KVStoreResultSet>	Promise used to return the KVStoreResultSet object obtained.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100001	Over max limits.
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  let resultSet: distributedKVStore.KVStoreResultSet = xxx;
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_string_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.STRING,
        value: 'batch_test_string_value'
      }
    }
    entries.push(entry);
  }
  kvStore.putBatch(entries).then(async () => {
    console.info('Succeeded in putting batch');
  }).catch((err: BusinessError) => {
    console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
  });
  const query = new distributedKVStore.Query();
  query.prefixKey("batch_test");
  kvStore.getResultSet(query).then((result) => {
    console.info('Succeeded in getting result set');
    resultSet = result;
  }).catch((err: BusinessError) => {
    console.error(`Failed to get resultset.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}

getResultSet

getResultSet(predicates: dataSharePredicates.DataSharePredicates, callback: AsyncCallback<KVStoreResultSet>): void

Obtains a KVStoreResultSet object that matches the specified predicate object. This API uses an asynchronous callback to return the result.

Model restriction: This API can be used only in the stage model.

System API: This is a system API.

System capability: SystemCapability.DistributedDataManager.DataShare.Provider

Parameters

Name	Type	Mandatory	Description
predicates	dataSharePredicates.DataSharePredicates	Yes	DataSharePredicates object that specifies the KVStoreResultSet object to obtain. If this parameter is null, define the processing logic.
callback	AsyncCallback<KVStoreResultSet>	Yes	Callback invoked to return the KVStoreResultSet object obtained.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100001	Over max limits.
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import dataSharePredicates from '@ohos.data.dataSharePredicates';
import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  let resultSet: distributedKVStore.KVStoreResultSet = xxx;
  let predicates = new dataSharePredicates.DataSharePredicates();
  predicates.prefixKey("batch_test_string_key");
  kvStore.getResultSet(predicates, async (err, result) => {
    if (err != undefined) {
      console.error(`Failed to get resultset.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in getting result set');
    resultSet = result;
    kvStore.closeResultSet(resultSet, (err) => {
      if (err != undefined) {
        console.error(`Failed to close resultset.code is ${err.code},message is ${err.message}`);
        return;
      }
      console.info('Succeeded in closing result set');
    })
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}

getResultSet

getResultSet(predicates: dataSharePredicates.DataSharePredicates): Promise<KVStoreResultSet>

Obtains a KVStoreResultSet object that matches the specified predicate object. This API uses a promise to return the result.

Model restriction: This API can be used only in the stage model.

System API: This is a system API.

System capability: SystemCapability.DistributedDataManager.DataShare.Provider

Parameters

Name	Type	Mandatory	Description
predicates	dataSharePredicates.DataSharePredicates	Yes	DataSharePredicates object that specifies the KVStoreResultSet object to obtain. If this parameter is null, define the processing logic.

Return value

Type	Description
Promise<KVStoreResultSet>	Promise that returns no value.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100001	Over max limits.
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import dataSharePredicates from '@ohos.data.dataSharePredicates';
import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  let resultSet: distributedKVStore.KVStoreResultSet = xxx;
  let predicates = new dataSharePredicates.DataSharePredicates();
  predicates.prefixKey("batch_test_string_key");
  kvStore.getResultSet(predicates).then((result) => {
    console.info('Succeeded in getting result set');
    resultSet = result;
  }).catch((err: BusinessError) => {
    console.error(`Failed to get resultset.code is ${err.code},message is ${err.message}`);
  });
  kvStore.closeResultSet(resultSet).then(() => {
    console.info('Succeeded in closing result set');
  }).catch((err: BusinessError) => {
    console.error(`Failed to close resultset.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}

closeResultSet

closeResultSet(resultSet: KVStoreResultSet, callback: AsyncCallback<void>): void

Closes the KVStoreResultSet object returned by SingleKvStore.getResultSet. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
resultSet	KVStoreResultSet	Yes	KVStoreResultSet object to close.
callback	AsyncCallback<void>	Yes	Callback invoked to return the result.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  let resultSet: distributedKVStore.KVStoreResultSet = xxx;
  kvStore.closeResultSet(resultSet, (err) => {
    if (err == undefined) {
      console.info('Succeeded in closing result set');
    } else {
      console.error(`Failed to close resultset.code is ${err.code},message is ${err.message}`);
    }
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}

closeResultSet

closeResultSet(resultSet: KVStoreResultSet): Promise<void>

Closes the KVStoreResultSet object returned by SingleKvStore.getResultSet. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
resultSet	KVStoreResultSet	Yes	KVStoreResultSet object to close.

Return value

Type	Description
Promise<void>	Promise that returns no value.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  let resultSet: distributedKVStore.KVStoreResultSet = xxx;
  kvStore.closeResultSet(resultSet).then(() => {
    console.info('Succeeded in closing result set');
  }).catch((err: BusinessError) => {
    console.error(`Failed to close resultset.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}

getResultSize

getResultSize(query: Query, callback: AsyncCallback<number>): void

Obtains the number of results that matches the specified Query object. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
query	Query	Yes	Query object to match.
callback	AsyncCallback<number>	Yes	Callback invoked to return the number of results obtained.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_string_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.STRING,
        value: 'batch_test_string_value'
      }
    }
    entries.push(entry);
  }
  kvStore.putBatch(entries, async (err) => {
    console.info('Succeeded in putting batch');
    const query = new distributedKVStore.Query();
    query.prefixKey("batch_test");
    kvStore.getResultSize(query, async (err, resultSize) => {
      if (err != undefined) {
        console.error(`Failed to get result size.code is ${err.code},message is ${err.message}`);
        return;
      }
      console.info('Succeeded in getting result set size');
    });
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}

getResultSize

getResultSize(query: Query): Promise<number>

Obtains the number of results that matches the specified Query object. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
query	Query	Yes	Query object to match.

Return value

Type	Description
Promise<number>	Promise used to return the number of results obtained.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_string_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.STRING,
        value: 'batch_test_string_value'
      }
    }
    entries.push(entry);
  }
  kvStore.putBatch(entries).then(async () => {
    console.info('Succeeded in putting batch');
  }).catch((err: BusinessError) => {
    console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
  });
  const query = new distributedKVStore.Query();
  query.prefixKey("batch_test");
  kvStore.getResultSize(query).then((resultSize) => {
    console.info('Succeeded in getting result set size');
  }).catch((err: BusinessError) => {
    console.error(`Failed to get result size.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}

backup

backup(file:string, callback: AsyncCallback<void>):void

Backs up a distributed KV store. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
file	string	Yes	Name of the KV store. The value cannot be empty or exceed MAX_KEY_LENGTH.
callback	AsyncCallback<void>	Yes	Callback invoked to return the result. If the operation is successful, err is undefined. Otherwise, err is an error object.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

let file = "BK001";
try {
  kvStore.backup(file, (err) => {
    if (err) {
      console.error(`Failed to backup.code is ${err.code},message is ${err.message} `);
    } else {
      console.info(`Succeeded in backupping data`);
    }
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

backup

backup(file:string): Promise<void>

Backs up an RDB store. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
file	string	Yes	Name of the KV store. The value cannot be empty or exceed MAX_KEY_LENGTH.

Return value

Type	Description
Promise<void>	Promise that returns no value.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

let file = "BK001";
try {
  kvStore.backup(file).then(() => {
    console.info(`Succeeded in backupping data`);
  }).catch((err: BusinessError) => {
    console.error(`Failed to backup.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

restore

restore(file:string, callback: AsyncCallback<void>):void

Restores a distributed KV store from a database file. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
file	string	Yes	Name of the database file. The value cannot be empty or exceed MAX_KEY_LENGTH.
callback	AsyncCallback<void>	Yes	Callback invoked to return the result. If the operation is successful, err is undefined. Otherwise, err is an error object.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

let file = "BK001";
try {
  kvStore.restore(file, (err) => {
    if (err) {
      console.error(`Failed to restore.code is ${err.code},message is ${err.message}`);
    } else {
      console.info(`Succeeded in restoring data`);
    }
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

restore

restore(file:string): Promise<void>

Restores a distributed KV store from a database file. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
file	string	Yes	Name of the database file. The value cannot be empty or exceed MAX_KEY_LENGTH.

Return value

Type	Description
Promise<void>	Promise that returns no value.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

let file = "BK001";
try {
  kvStore.restore(file).then(() => {
    console.info(`Succeeded in restoring data`);
  }).catch((err: BusinessError) => {
    console.error(`Failed to restore.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

deleteBackup

deleteBackup(files:Array<string>, callback: AsyncCallback<Array<[string, number]>>):void

Deletes a backup file. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
files	Array<string>	Yes	Name of the backup file to delete. The value cannot be empty or exceed MAX_KEY_LENGTH.
callback	AsyncCallback<Array<[string, number]>>	Yes	Callback invoked to return the name of the backup file deleted and the operation result.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

let files = ["BK001", "BK002"];
try {
  kvStore.deleteBackup(files, (err, data) => {
    if (err) {
      console.error(`Failed to delete Backup.code is ${err.code},message is ${err.message}`);
    } else {
      console.info(`Succeed in deleting Backup.data=${data}`);
    }
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

deleteBackup

deleteBackup(files:Array<string>): Promise<Array<[string, number]>>

Deletes a backup file. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
files	Array<string>	Yes	Name of the backup file to delete. The value cannot be empty or exceed MAX_KEY_LENGTH.

Return value

Type	Description
Promise<Array<[string, number]>>	Promise used to return the name of the backup file deleted and the operation result.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

let files = ["BK001", "BK002"];
try {
  kvStore.deleteBackup(files).then((data) => {
    console.info(`Succeed in deleting Backup.data=${data}`);
  }).catch((err: BusinessError) => {
    console.error(`Failed to delete Backup.code is ${err.code},message is ${err.message}`);
  })
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

startTransaction

startTransaction(callback: AsyncCallback<void>): void

Starts the transaction in this single KV store. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
callback	AsyncCallback<void>	Yes	Callback invoked to return the result.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100005	Database or result set already closed.

For details about the error codes, see RDB Error Codes.

ID	Error Message
14800047	The WAL file size exceeds the default limit.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

function putBatchString(len: number, prefix: string) {
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < len; i++) {
    let entry: distributedKVStore.Entry = {
      key: prefix + i,
      value: {
        type: distributedKVStore.ValueType.STRING,
        value: 'batch_test_string_value'
      }
    }
    entries.push(entry);
  }
  return entries;
}

try {
  let count = 0;
  kvStore.on('dataChange', 0, (data) => {
    console.info(`startTransaction 0 ${data}`);
    count++;
  });
  kvStore.startTransaction(async (err) => {
    if (err != undefined) {
      console.error(`Failed to start Transaction.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in starting Transaction');
    let entries = putBatchString(10, 'batch_test_string_key');
    console.info(`entries: ${entries}`);
    kvStore.putBatch(entries, async (err) => {
      if (err != undefined) {
        console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
        return;
      }
      console.info('Succeeded in putting Batch');
    });
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to start Transaction.code is ${error.code},message is ${error.message}`);
}

startTransaction

startTransaction(): Promise<void>

Starts the transaction in this single KV store. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Type	Description
Promise<void>	Promise that returns no value.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100005	Database or result set already closed.

For details about the error codes, see RDB Error Codes.

ID	Error Message
14800047	The WAL file size exceeds the default limit.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  let count = 0;
  kvStore.on('dataChange', distributedKVStore.SubscribeType.SUBSCRIBE_TYPE_ALL, (data) => {
    console.info(`startTransaction 0 ${data}`);
    count++;
  });
  kvStore.startTransaction().then(async () => {
    console.info('Succeeded in starting Transaction');
  }).catch((err: BusinessError) => {
    console.error(`Failed to start Transaction.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to start Transaction.code is ${error.code},message is ${error.message}`);
}

commit

commit(callback: AsyncCallback<void>): void

Commits the transaction in this single KV store. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
callback	AsyncCallback<void>	Yes	Callback invoked to return the result.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  kvStore.commit((err) => {
    if (err == undefined) {
      console.info('Succeeded in committing');
    } else {
      console.error(`Failed to commit.code is ${err.code},message is ${err.message}`);
    }
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

commit

commit(): Promise<void>

Commits the transaction in this single KV store. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Type	Description
Promise<void>	Promise that returns no value.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  kvStore.commit().then(async () => {
    console.info('Succeeded in committing');
  }).catch((err: BusinessError) => {
    console.error(`Failed to commit.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

rollback

rollback(callback: AsyncCallback<void>): void

Rolls back the transaction in this single KV store. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
callback	AsyncCallback<void>	Yes	Callback invoked to return the result.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  kvStore.rollback((err) => {
    if (err == undefined) {
      console.info('Succeeded in rolling back');
    } else {
      console.error(`Failed to rollback.code is ${err.code},message is ${err.message}`);
    }
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

rollback

rollback(): Promise<void>

Rolls back the transaction in this single KV store. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Type	Description
Promise<void>	Promise that returns no value.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  kvStore.rollback().then(async () => {
    console.info('Succeeded in rolling back');
  }).catch((err: BusinessError) => {
    console.error(`Failed to rollback.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

enableSync

enableSync(enabled: boolean, callback: AsyncCallback<void>): void

Sets data synchronization, which can be enabled or disabled. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
enabled	boolean	Yes	Whether to enable data synchronization. The value true means to enable data synchronization, and false means the opposite.
callback	AsyncCallback<void>	Yes	Callback invoked to return the result.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  kvStore.enableSync(true, (err) => {
    if (err == undefined) {
      console.info('Succeeded in enabling sync');
    } else {
      console.error(`Failed to enable sync.code is ${err.code},message is ${err.message}`);
    }
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

enableSync

enableSync(enabled: boolean): Promise<void>

Sets data synchronization, which can be enabled or disabled. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
enabled	boolean	Yes	Whether to enable data synchronization. The value true means to enable data synchronization, and false means the opposite.

Return value

Type	Description
Promise<void>	Promise that returns no value.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  kvStore.enableSync(true).then(() => {
    console.info('Succeeded in enabling sync');
  }).catch((err: BusinessError) => {
    console.error(`Failed to enable sync.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

setSyncRange

setSyncRange(localLabels: string[], remoteSupportLabels: string[], callback: AsyncCallback<void>): void

Sets the data synchronization range. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
localLabels	string[]	Yes	Synchronization labels set for the local device.
remoteSupportLabels	string[]	Yes	Synchronization labels set for remote devices.
callback	AsyncCallback<void>	Yes	Callback invoked to return the result.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  const localLabels = ['A', 'B'];
  const remoteSupportLabels = ['C', 'D'];
  kvStore.setSyncRange(localLabels, remoteSupportLabels, (err) => {
    if (err != undefined) {
      console.error(`Failed to set syncRange.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in setting syncRange');
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

setSyncRange

setSyncRange(localLabels: string[], remoteSupportLabels: string[]): Promise<void>

Sets the data synchronization range. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
localLabels	string[]	Yes	Synchronization labels set for the local device.
remoteSupportLabels	string[]	Yes	Synchronization labels set for remote devices.

Return value

Type	Description
Promise<void>	Promise that returns no value.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  const localLabels = ['A', 'B'];
  const remoteSupportLabels = ['C', 'D'];
  kvStore.setSyncRange(localLabels, remoteSupportLabels).then(() => {
    console.info('Succeeded in setting syncRange');
  }).catch((err: BusinessError) => {
    console.error(`Failed to set syncRange.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

setSyncParam

setSyncParam(defaultAllowedDelayMs: number, callback: AsyncCallback<void>): void

Sets the default delay allowed for KV store synchronization. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
defaultAllowedDelayMs	number	Yes	Default delay allowed for database synchronization, in ms.
callback	AsyncCallback<void>	Yes	Callback invoked to return the result.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  const defaultAllowedDelayMs = 500;
  kvStore.setSyncParam(defaultAllowedDelayMs, (err) => {
    if (err != undefined) {
      console.error(`Failed to set syncParam.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in setting syncParam');
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

setSyncParam

setSyncParam(defaultAllowedDelayMs: number): Promise<void>

Sets the default delay allowed for KV store synchronization. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
defaultAllowedDelayMs	number	Yes	Default delay allowed for database synchronization, in ms.

Return value

Type	Description
Promise<void>	Promise that returns no value.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  const defaultAllowedDelayMs = 500;
  kvStore.setSyncParam(defaultAllowedDelayMs).then(() => {
    console.info('Succeeded in setting syncParam');
  }).catch((err: BusinessError) => {
    console.error(`Failed to set syncParam.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

sync

sync(deviceIds: string[], mode: SyncMode, delayMs?: number): void

Synchronizes the KV store manually. For details about the synchronization modes of KV stores, see Cross-Device Synchronization of KV Stores. > NOTE > > deviceIds is networkId in DeviceBasicInfo, which can be obtained by deviceManager.getAvailableDeviceListSync.

Required permissions: ohos.permission.DISTRIBUTED_DATASYNC

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
deviceIds	string[]	Yes	List of networkIds of the devices in the same networking environment to be synchronized.
mode	SyncMode	Yes	Synchronization mode.
delayMs	number	No	Allowed synchronization delay time, in ms. The default value is 0.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100004	Not found.

Example

import deviceManager from '@ohos.distributedDeviceManager';
import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

let devManager: deviceManager.DeviceManager;
const KEY_TEST_SYNC_ELEMENT = 'key_test_sync';
const VALUE_TEST_SYNC_ELEMENT = 'value-string-001';
// create deviceManager
try {
  devManager = deviceManager.createDeviceManager(context.applicationInfo.name);
  let deviceIds: string[] = [];
  if (devManager != null) {
    let devices = devManager.getAvailableDeviceListSync();
    for (let i = 0; i < devices.length; i++) {
      deviceIds[i] = devices[i].networkId as string;
    }
  }
  try {
    kvStore.on('syncComplete', (data) => {
      console.info('Sync dataChange');
    });
    kvStore.put(KEY_TEST_SYNC_ELEMENT + 'testSync101', VALUE_TEST_SYNC_ELEMENT, (err) => {
      if (err != undefined) {
        console.error(`Failed to sync.code is ${err.code},message is ${err.message}`);
        return;
      }
      console.info('Succeeded in putting data');
      const mode = distributedKVStore.SyncMode.PULL_ONLY;
      kvStore.sync(deviceIds, mode, 1000);
    });
  } catch (e) {
    let error = e as BusinessError;
    console.error(`Failed to sync.code is ${error.code},message is ${error.message}`);
  }

} catch (err) {
  let error = err as BusinessError;
  console.error("createDeviceManager errCode:" + error.code + ",errMessage:" + error.message);
}

sync

sync(deviceIds: string[], query: Query, mode: SyncMode, delayMs?: number): void

Synchronizes the KV store manually. This API returns the result synchronously. For details about the synchronization modes of KV stores, see Cross-Device Synchronization of KV Stores. > NOTE > > deviceIds is networkId in DeviceBasicInfo, which can be obtained by deviceManager.getAvailableDeviceListSync.

Required permissions: ohos.permission.DISTRIBUTED_DATASYNC

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
deviceIds	string[]	Yes	List of networkIds of the devices in the same networking environment to be synchronized.
mode	SyncMode	Yes	Synchronization mode.
query	Query	Yes	Query object to match.
delayMs	number	No	Allowed synchronization delay time, in ms. The default value is 0.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100004	Not found.

Example

import deviceManager from '@ohos.distributedDeviceManager';
import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

let devManager: deviceManager.DeviceManager;
const KEY_TEST_SYNC_ELEMENT = 'key_test_sync';
const VALUE_TEST_SYNC_ELEMENT = 'value-string-001';
// create deviceManager
try {
  let devManager = deviceManager.createDeviceManager(context.applicationInfo.name);
  let deviceIds: string[] = [];
  if (devManager != null) {
    let devices = devManager.getAvailableDeviceListSync();
    for (let i = 0; i < devices.length; i++) {
      deviceIds[i] = devices[i].networkId as string;
    }
  }
  try {
    kvStore.on('syncComplete', (data) => {
      console.info('Sync dataChange');
    });
    kvStore.put(KEY_TEST_SYNC_ELEMENT + 'testSync101', VALUE_TEST_SYNC_ELEMENT, (err) => {
      if (err != undefined) {
        console.error(`Failed to sync.code is ${err.code},message is ${err.message}`);
        return;
      }
      console.info('Succeeded in putting data');
      const mode = distributedKVStore.SyncMode.PULL_ONLY;
      const query = new distributedKVStore.Query();
      query.prefixKey("batch_test");
      query.deviceId(devManager.getLocalDeviceNetworkId());
      kvStore.sync(deviceIds, query, mode, 1000);
    });
  } catch (e) {
    let error = e as BusinessError;
    console.error(`Failed to sync.code is ${error.code},message is ${error.message}`);
  }

} catch (err) {
  let error = err as BusinessError;
  console.error("createDeviceManager errCode:" + error.code + ",errMessage:" + error.message);
}

on(‘dataChange’)

on(event: ‘dataChange’, type: SubscribeType, listener: Callback<ChangeNotification>): void

Subscribes to data changes of the specified type.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
event	string	Yes	Event type. The value is dataChange, which indicates data changes.
type	SubscribeType	Yes	Type of data change.
listener	Callback<ChangeNotification>	Yes	Callback invoked to return the data change.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100001	Over max limits.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  kvStore.on('dataChange', distributedKVStore.SubscribeType.SUBSCRIBE_TYPE_LOCAL, (data) => {
    console.info(`dataChange callback call data: ${data}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

on(‘syncComplete’)

on(event: ‘syncComplete’, syncCallback: Callback<Array<[string, number]>>): void

Subscribes to synchronization complete events.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
event	string	Yes	Event type. The value is syncComplete, which indicates a synchronization complete event.
syncCallback	Callback<Array<[string, number]>>	Yes	Callback invoked to return the synchronization complete event.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

const KEY_TEST_FLOAT_ELEMENT = 'key_test_float';
const VALUE_TEST_FLOAT_ELEMENT = 321.12;
try {
  kvStore.on('syncComplete', (data) => {
    console.info(`syncComplete ${data}`);
  });
  kvStore.put(KEY_TEST_FLOAT_ELEMENT, VALUE_TEST_FLOAT_ELEMENT).then(() => {
    console.info('succeeded in putting');
  }).catch((err: BusinessError) => {
    console.error(`Failed to put.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to subscribe syncComplete.code is ${error.code},message is ${error.message}`);
}

off(‘dataChange’)

off(event:‘dataChange’, listener?: Callback<ChangeNotification>): void

Unsubscribes from data changes.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
event	string	Yes	Event type. The value is dataChange, which indicates data changes.
listener	Callback<ChangeNotification>	No	Callback for the data change. If the callback is not specified, all callbacks for dataChange will be unregistered.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

class KvstoreModel {
  call(data: string) {
    console.info(`dataChange : ${data}`);
  }

  subscribeDataChange() {
    try {
      if (kvStore != null) {
        kvStore.on('dataChange', distributedKVStore.SubscribeType.SUBSCRIBE_TYPE_REMOTE, this.call);
      }
    } catch (err) {
      let error = err as BusinessError;
      console.error(`Failed to subscribeDataChange.code is ${error.code},message is ${error.message}`);
    }
  }

  unsubscribeDataChange() {
    try {
      if (kvStore != null) {
        kvStore.off('dataChange', this.call);
      }
    } catch (err) {
      let error = err as BusinessError;
      console.error(`Failed to unsubscribeDataChange.code is ${error.code},message is ${error.message}`);
    }
  }
}

off(‘syncComplete’)

off(event: ‘syncComplete’, syncCallback?: Callback<Array<[string, number]>>): void

Unsubscribes from synchronization complete events.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
event	string	Yes	Event type. The value is syncComplete, which indicates a synchronization complete event.
syncCallback	Callback<Array<[string, number]>>	No	Callback for the synchronization complete event. If the callback is not specified, all callbacks for syncComplete will be unregistered.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

class KvstoreModel {
  call(data: string) {
    console.info(`syncComplete : ${data}`);
  }

  subscribeDataChange() {
    try {
      if (kvStore != null) {
        kvStore.on('syncComplete', distributedKVStore.SubscribeType.SUBSCRIBE_TYPE_REMOTE, this.call);
      }
    } catch (err) {
      let error = err as BusinessError;
      console.error(`Failed to subscribeDataChange.code is ${error.code},message is ${error.message}`);
    }
  }

  unsubscribeDataChange() {
    try {
      if (kvStore != null) {
        kvStore.off('dsyncComplete', this.call);
      }
    } catch (err) {
      let error = err as BusinessError;
      console.error(`Failed to unsubscribeDataChange.code is ${error.code},message is ${error.message}`);
    }
  }
}

getSecurityLevel

getSecurityLevel(callback: AsyncCallback<SecurityLevel>): void

Obtains the security level of this KV store. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
callback	AsyncCallback<SecurityLevel>	Yes	Callback invoked to return the security level obtained.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  kvStore.getSecurityLevel((err, data) => {
    if (err != undefined) {
      console.error(`Failed to get SecurityLevel.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in getting securityLevel');
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

getSecurityLevel

getSecurityLevel(): Promise<SecurityLevel>

Obtains the security level of this KV store. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Type	Description
Promise<SecurityLevel>	Promise used to return the security level obtained.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.SingleKVStore = xxx;

try {
  kvStore.getSecurityLevel().then((data) => {
    console.info('Succeeded in getting securityLevel');
  }).catch((err: BusinessError) => {
    console.error(`Failed to get SecurityLevel.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

DeviceKVStore

Provides APIs for querying and synchronizing data in a device KV store. This class inherits from SingleKVStore.

Data is distinguished by device in a device KV store. Each device can only write and modify its own data. Data of other devices is read-only and cannot be modified.

For example, a device KV store can be used to implement image sharing between devices. The images of other devices can be viewed, but not be modified or deleted.

Before calling any method in DeviceKVStore, you must use getKVStore to obtain a DeviceKVStore object.

get

get(key: string, callback: AsyncCallback<boolean|string|number|Uint8Array>): void

Obtains the value of the specified key for this device. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
key	string	Yes	Key of the value to obtain. It cannot be empty, and the length cannot exceed MAX_KEY_LENGTH.
callback	AsyncCallback<boolean |string |number |Uint8Array>	Yes	Callback invoked to return the value obtained.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100004	Not found.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.DeviceKVStore = xxx;

const KEY_TEST_STRING_ELEMENT = 'key_test_string';
const VALUE_TEST_STRING_ELEMENT = 'value-test-string';
try {
  kvStore.put(KEY_TEST_STRING_ELEMENT, VALUE_TEST_STRING_ELEMENT, (err) => {
    if (err != undefined) {
      console.error(`Failed to put.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info("Succeeded in putting");
    kvStore.get(KEY_TEST_STRING_ELEMENT, (err, data) => {
      if (err != undefined) {
        console.error(`Failed to get.code is ${err.code},message is ${err.message}`);
        return;
      }
      console.info(`Succeeded in getting data.data=${data}`);
    });
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to get.code is ${error.code},message is ${error.message}`);
}

get

get(key: string): Promise<boolean|string|number|Uint8Array>

Obtains the value of the specified key for this device. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
key	string	Yes	Key of the value to obtain. It cannot be empty, and the length cannot exceed MAX_KEY_LENGTH.

Return value

Type	Description
Promise<Uint8Array |string |boolean |number>	Promise used to return the value obtained.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100004	Not found.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.DeviceKVStore = xxx;

const KEY_TEST_STRING_ELEMENT = 'key_test_string';
const VALUE_TEST_STRING_ELEMENT = 'value-test-string';
try {
  kvStore.put(KEY_TEST_STRING_ELEMENT, VALUE_TEST_STRING_ELEMENT).then(() => {
    console.info(`Succeeded in putting data`);
    kvStore.get(KEY_TEST_STRING_ELEMENT).then((data) => {
      console.info(`Succeeded in getting data.data=${data}`);
    }).catch((err: BusinessError) => {
      console.error(`Failed to get.code is ${err.code},message is ${err.message}`);
    });
  }).catch((err: BusinessError) => {
    console.error(`Failed to put.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to get.code is ${error.code},message is ${error.message}`);
}

get

get(deviceId: string, key: string, callback: AsyncCallback<boolean|string|number|Uint8Array>): void

Obtains a string value that matches the specified device ID and key. This API uses an asynchronous callback to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Name	Type	Mandatory	Description
deviceId	string	Yes	ID of the target device.
key	string	Yes	Key to match.
callback	AsyncCallback<boolean|string|number|Uint8Array>	Yes	Callback invoked to return the value obtained.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100004	Not found.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.DeviceKVStore = xxx;

const KEY_TEST_STRING_ELEMENT = 'key_test_string_2';
const VALUE_TEST_STRING_ELEMENT = 'value-string-002';
try {
  kvStore.put(KEY_TEST_STRING_ELEMENT, VALUE_TEST_STRING_ELEMENT, async (err) => {
    if (err != undefined) {
      console.error(`Failed to put.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in putting');
    kvStore.get('localDeviceId', KEY_TEST_STRING_ELEMENT, (err, data) => {
      if (err != undefined) {
        console.error(`Failed to get.code is ${err.code},message is ${err.message}`);
        return;
      }
      console.info('Succeeded in getting');
    });
  })
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to get.code is ${error.code},message is ${error.message}`);
}

get

get(deviceId: string, key: string): Promise<boolean|string|number|Uint8Array>

Obtains a string value that matches the specified device ID and key. This API uses a promise to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Name	Type	Mandatory	Description
deviceId	string	Yes	ID of the target device.
key	string	Yes	Key to match.

Return value

Type	Description
Promise<boolean|string|number|Uint8Array>	Promise used to return the string value that matches the given condition.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100004	Not found.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.DeviceKVStore = xxx;

const KEY_TEST_STRING_ELEMENT = 'key_test_string_2';
const VALUE_TEST_STRING_ELEMENT = 'value-string-002';
try {
  kvStore.put(KEY_TEST_STRING_ELEMENT, VALUE_TEST_STRING_ELEMENT).then(async () => {
    console.info('Succeeded in putting');
    kvStore.get('localDeviceId', KEY_TEST_STRING_ELEMENT).then((data) => {
      console.info('Succeeded in getting');
    }).catch((err: BusinessError) => {
      console.error(`Failed to get.code is ${err.code},message is ${err.message}`);
    });
  }).catch((error: BusinessError) => {
    console.error(`Failed to put.code is ${error.code},message is ${error.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to get.code is ${error.code},message is ${error.message}`);
}

getEntries

getEntries(keyPrefix: string, callback: AsyncCallback<Entry[]>): void

Obtains all KV pairs that match the specified key prefix for this device. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
keyPrefix	string	Yes	Key prefix to match.
callback	AsyncCallback<Entry[]>	Yes	Callback invoked to return the KV pairs that match the specified prefix.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.DeviceKVStore = xxx;

try {
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_string_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.STRING,
        value: 'batch_test_string_value'
      }
    }
    entries.push(entry);
  }
  console.info(`entries: ${entries}`);
  kvStore.putBatch(entries, async (err) => {
    if (err != undefined) {
      console.error(`Failed to put Batch.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in putting Batch');
    kvStore.getEntries('batch_test_string_key', (err, entries) => {
      if (err != undefined) {
        console.error(`Failed to get Entries.code is ${err.code},message is ${err.message}`);
        return;
      }
      console.info('Succeeded in getting Entries');
      console.info(`entries.length: ${entries.length}`);
      console.info(`entries[0]: ${entries[0]}`);
    });
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message} `);
}

getEntries

getEntries(keyPrefix: string): Promise<Entry[]>

Obtains all KV pairs that match the specified key prefix for this device. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
keyPrefix	string	Yes	Key prefix to match.

Return value

Type	Description
Promise<Entry[]>	Promise used to return the KV pairs that match the specified prefix.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.DeviceKVStore = xxx;

try {
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_string_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.STRING,
        value: 'batch_test_string_value'
      }
    }
    entries.push(entry);
  }
  console.info(`entries: ${entries}`);
  kvStore.putBatch(entries).then(async () => {
    console.info('Succeeded in putting Batch');
    kvStore.getEntries('batch_test_string_key').then((entries) => {
      console.info('Succeeded in getting Entries');
      console.info(`PutBatch ${entries}`);
    }).catch((err: BusinessError) => {
      console.error(`Failed to get Entries.code is ${err.code},message is ${err.message}`);
    });
  }).catch((err: BusinessError) => {
    console.error(`Failed to put Batch.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message} `);
}

getEntries

getEntries(deviceId: string, keyPrefix: string, callback: AsyncCallback<Entry[]>): void

Obtains all KV pairs that match the specified device ID and key prefix. This API uses an asynchronous callback to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Name	Type	Mandatory	Description
deviceId	string	Yes	ID of the target device.
keyPrefix	string	Yes	Key prefix to match.
callback	AsyncCallback<Entry[]>	Yes	Callback invoked to return the KV pairs obtained.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.DeviceKVStore = xxx;

try {
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_string_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.STRING,
        value: 'batch_test_string_value'
      }
    }
    entries.push(entry);
  }
  console.info(`entries : ${entries}`);
  kvStore.putBatch(entries, async (err) => {
    if (err != undefined) {
      console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in putting batch');
    kvStore.getEntries('localDeviceId', 'batch_test_string_key', (err, entries) => {
      if (err != undefined) {
        console.error(`Failed to get entries.code is ${err.code},message is ${err.message}`);
        return;
      }
      console.info('Succeeded in getting entries');
      console.info(`entries.length: ${entries.length}`);
      console.info(`entries[0]: ${entries[0]}`);
    });
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to put batch.code is ${error.code},message is ${error.message}`);
}

getEntries

getEntries(deviceId: string, keyPrefix: string): Promise<Entry[]>

Obtains all KV pairs that match the specified device ID and key prefix. This API uses a promise to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Name	Type	Mandatory	Description
deviceId	string	Yes	ID of the target device.
keyPrefix	string	Yes	Key prefix to match.

Return value

Type	Description
Promise<Entry[]>	Promise used to return all the KV pairs that match the given condition.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.DeviceKVStore = xxx;

try {
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_string_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.STRING,
        value: 'batch_test_string_value'
      }
    }
    entries.push(entry);
  }
  console.info(`entries: ${entries}`);
  kvStore.putBatch(entries).then(async () => {
    console.info('Succeeded in putting batch');
    kvStore.getEntries('localDeviceId', 'batch_test_string_key').then((entries) => {
      console.info('Succeeded in getting entries');
      console.info(`entries.length: ${entries.length}`);
      console.info(`entries[0]: ${entries[0]}`);
      console.info(`entries[0].value: ${entries[0].value}`);
      console.info(`entries[0].value.value: ${entries[0].value.value}`);
    }).catch((err: BusinessError) => {
      console.error(`Failed to get entries.code is ${err.code},message is ${err.message}`);
    });
  }).catch((err: BusinessError) => {
    console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to put batch.code is ${error.code},message is ${error.message}`);
}

getEntries

getEntries(query: Query, callback: AsyncCallback<Entry[]>): void

Obtains all KV pairs that match the specified Query object for this device. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
query	Query	Yes	Key prefix to match.
callback	AsyncCallback<Entry[]>	Yes	Callback invoked to return the KV pairs that match the specified Query object on the local device.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.DeviceKVStore = xxx;

try {
  let arr = new Uint8Array([21, 31]);
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_bool_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.BYTE_ARRAY,
        value: arr
      }
    }
    entries.push(entry);
  }
  console.info(`entries: {entries}`);
  kvStore.putBatch(entries, async (err) => {
    console.info('Succeeded in putting Batch');
    const query = new distributedKVStore.Query();
    query.prefixKey("batch_test");
    kvStore.getEntries(query, (err, entries) => {
      if (err != undefined) {
        console.error(`Failed to get Entries.code is ${err.code},message is ${err.message}`);
        return;
      }
      console.info('Succeeded in getting Entries');
      console.info(`entries.length: ${entries.length}`);
      console.info(`entries[0]: ${entries[0]}`);
    });
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to get Entries.code is ${error.code},message is ${error.message}`);
}

getEntries

getEntries(query: Query): Promise<Entry[]>

Obtains all KV pairs that match the specified Query object for this device. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
query	Query	Yes	Query object to match.

Return value

Type	Description
Promise<Entry[]>	Promise used to return the KV pairs that match the specified Query object on the local device.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.DeviceKVStore = xxx;

try {
  let arr = new Uint8Array([21, 31]);
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_bool_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.BYTE_ARRAY,
        value: arr
      }
    }
    entries.push(entry);
  }
  console.info(`entries: {entries}`);
  kvStore.putBatch(entries).then(async () => {
    console.info('Succeeded in putting Batch');
    const query = new distributedKVStore.Query();
    query.prefixKey("batch_test");
    kvStore.getEntries(query).then((entries) => {
      console.info('Succeeded in getting Entries');
    }).catch((err: BusinessError) => {
      console.error(`Failed to get Entries.code is ${err.code},message is ${err.message}`);
    });
  }).catch((err: BusinessError) => {
    console.error(`Failed to get Entries.code is ${err.code},message is ${err.message}`)
  });
  console.info('Succeeded in getting Entries');
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to get Entries.code is ${error.code},message is ${error.message}`);
}

getEntries

getEntries(deviceId: string, query: Query, callback: AsyncCallback<Entry[]>): void

Obtains the KV pairs that match the specified device ID and Query object. This API uses an asynchronous callback to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Name	Type	Mandatory	Description
deviceId	string	Yes	ID of the target device.
query	Query	Yes	Query object to match.
callback	AsyncCallback<Entry[]>	Yes	Callback invoked to return the KV pairs that match the specified device ID and Query object.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
  let arr = new Uint8Array([21, 31]);
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_bool_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.BYTE_ARRAY,
        value: arr
      }
    }
    entries.push(entry);
  }
  console.info(`entries: ${entries}`);
  kvStore.putBatch(entries, async (err) => {
    if (err != undefined) {
      console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in putting batch');
    let query = new distributedKVStore.Query();
    query.deviceId('localDeviceId');
    query.prefixKey("batch_test");
    kvStore.getEntries('localDeviceId', query, (err, entries) => {
      if (err != undefined) {
        console.error(`Failed to get entries.code is ${err.code},message is ${err.message}`);
        return;
      }
      console.info('Succeeded in getting entries');
      console.info(`entries.length: ${entries.length}`);
      console.info(`entries[0]: ${entries[0]}`);
    })
  });
  console.info('Succeeded in getting entries');
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to get entries.code is ${error.code},message is ${error.message}`);
}

getEntries

getEntries(deviceId: string, query: Query): Promise<Entry[]>

Obtains the KV pairs that match the specified device ID and Query object. This API uses a promise to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Name	Type	Mandatory	Description
deviceId	string	Yes	ID of the target device.
query	Query	Yes	Query object to match.

Return value

Type	Description
Promise<Entry[]>	Promise used to return the KV pairs that match the specified device ID and Query object.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
  let arr = new Uint8Array([21, 31]);
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_bool_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.BYTE_ARRAY,
        value: arr
      }
    }
    entries.push(entry);
  }
  console.info(`entries: ${entries}`);
  kvStore.putBatch(entries).then(async () => {
    console.info('Succeeded in putting batch');
    let query = new distributedKVStore.Query();
    query.deviceId('localDeviceId');
    query.prefixKey("batch_test");
    kvStore.getEntries('localDeviceId', query).then((entries) => {
      console.info('Succeeded in getting entries');
    }).catch((err: BusinessError) => {
      console.error(`Failed to get entries.code is ${err.code},message is ${err.message}`);
    });
  }).catch((err: BusinessError) => {
    console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
  });
  console.info('Succeeded in getting entries');
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to get entries.code is ${error.code},message is ${error.message}`);
}

getResultSet

getResultSet(keyPrefix: string, callback: AsyncCallback<KVStoreResultSet>): void

Obtains a result set with the specified prefix for this device. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
keyPrefix	string	Yes	Key prefix to match.
callback	AsyncCallback<KVStoreResultSet>	Yes	Callback invoked to return the result set with the specified prefix.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100001	Over max limits.
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
  let resultSet: distributedKVStore.KVStoreResultSet = xxx;
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_string_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.STRING,
        value: 'batch_test_string_value'
      }
    }
    entries.push(entry);
  }
  kvStore.putBatch(entries, async (err) => {
    if (err != undefined) {
      console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in putting batch');
    kvStore.getResultSet('batch_test_string_key', async (err, result) => {
      if (err != undefined) {
        console.error(`Failed to get resultset.code is ${err.code},message is ${err.message}`);
        return;
      }
      console.info('Succeeded in getting result set');
      resultSet = result;
      kvStore.closeResultSet(resultSet, (err) => {
        if (err != undefined) {
          console.error(`Failed to close resultset.code is ${err.code},message is ${err.message}`);
          return;
        }
        console.info('Succeeded in closing result set');
      })
    });
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.message}`);
}

getResultSet

getResultSet(keyPrefix: string): Promise<KVStoreResultSet>

Obtains a result set with the specified prefix for this device. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
keyPrefix	string	Yes	Key prefix to match.

Return value

Type	Description
Promise<KVStoreResultSet>	Promise used to return the result set with the specified prefix.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100001	Over max limits.
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
  let resultSet: distributedKVStore.KVStoreResultSet = xxx;
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_string_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.STRING,
        value: 'batch_test_string_value'
      }
    }
    entries.push(entry);
  }
  kvStore.putBatch(entries).then(async () => {
    console.info('Succeeded in putting batch');
  }).catch((err: BusinessError) => {
    console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
  });
  kvStore.getResultSet('batch_test_string_key').then((result) => {
    console.info('Succeeded in getting result set');
    resultSet = result;
  }).catch((err: BusinessError) => {
    console.error(`Failed to get resultset.code is ${err.code},message is ${err.message}`);
  });
  kvStore.closeResultSet(resultSet).then(() => {
    console.info('Succeeded in closing result set');
  }).catch((err: BusinessError) => {
    console.error(`Failed to close resultset.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}

getResultSet

getResultSet(deviceId: string, keyPrefix: string, callback: AsyncCallback<KVStoreResultSet>): void

Obtains a KVStoreResultSet object that matches the specified device ID and key prefix. This API uses an asynchronous callback to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Name	Type	Mandatory	Description
deviceId	string	Yes	ID of the target device.
keyPrefix	string	Yes	Key prefix to match.
callback	AsyncCallback<KVStoreResultSet>	Yes	Callback invoked to return the KVStoreResultSet object that matches the specified device ID and key prefix.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100001	Over max limits.
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
  let resultSet: distributedKVStore.KVStoreResultSet = xxx;
  kvStore.getResultSet('localDeviceId', 'batch_test_string_key', async (err, result) => {
    if (err != undefined) {
      console.error(`Failed to get resultSet.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in getting resultSet');
    resultSet = result;
    kvStore.closeResultSet(resultSet, (err) => {
      if (err != undefined) {
        console.error(`Failed to close resultSet.code is ${err.code},message is ${err.message}`);
        return;
      }
      console.info('Succeeded in closing resultSet');
    })
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to get resultSet.code is ${error.code},message is ${error.message}`);
}

getResultSet

getResultSet(deviceId: string, keyPrefix: string): Promise<KVStoreResultSet>

Obtains a KVStoreResultSet object that matches the specified device ID and key prefix. This API uses a promise to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Name	Type	Mandatory	Description
deviceId	string	Yes	ID of the target device.
keyPrefix	string	Yes	Key prefix to match.

Return value

Type	Description
Promise<KVStoreResultSet>	Promise used to return the KVStoreResultSet object that matches the specified device ID and key prefix.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100001	Over max limits.
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
  let resultSet: distributedKVStore.KVStoreResultSet = xxx;
  kvStore.getResultSet('localDeviceId', 'batch_test_string_key').then((result) => {
    console.info('Succeeded in getting resultSet');
    resultSet = result;
  }).catch((err: BusinessError) => {
    console.error(`Failed to get resultSet.code is ${err.code},message is ${err.message}`);
  });
  kvStore.closeResultSet(resultSet).then(() => {
    console.info('Succeeded in closing resultSet');
  }).catch((err: BusinessError) => {
    console.error(`Failed to close resultSet.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to get resultSet.code is ${error.code},message is ${error.message}`);
}

getResultSet

getResultSet(deviceId: string, query: Query, callback: AsyncCallback<KVStoreResultSet>): void

Obtains a KVStoreResultSet object that matches the specified device ID and Query object. This API uses an asynchronous callback to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Name	Type	Mandatory	Description
deviceId	string	Yes	ID of the device to which the KVStoreResultSet object belongs.
query	Query	Yes	Query object to match.
callback	AsyncCallback<KVStoreResultSet>	Yes	Callback invoked to return the KVStoreResultSet object that matches the specified device ID and Query object.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100001	Over max limits.
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
  let resultSet: distributedKVStore.KVStoreResultSet = xxx;
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_string_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.STRING,
        value: 'batch_test_string_value'
      }
    }
    entries.push(entry);
  }
  kvStore.putBatch(entries, async (err) => {
    if (err != undefined) {
      console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in putting batch');
    const query = new distributedKVStore.Query();
    query.prefixKey("batch_test");
    kvStore.getResultSet('localDeviceId', query, async (err, result) => {
      if (err != undefined) {
        console.error(`Failed to get resultSet.code is ${err.code},message is ${err.message}`);
        return;
      }
      console.info('Succeeded in getting resultSet');
      resultSet = result;
      kvStore.closeResultSet(resultSet, (err) => {
        if (err != undefined) {
          console.error(`Failed to close resultSet.code is ${err.code},message is ${err.message}`);
          return;
        }
        console.info('Succeeded in closing resultSet');
      })
    });
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to get resultSet.code is ${error.code},message is ${error.message}`);
}

getResultSet

getResultSet(deviceId: string, query: Query): Promise<KVStoreResultSet>

Obtains a KVStoreResultSet object that matches the specified device ID and Query object. This API uses a promise to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Name	Type	Mandatory	Description
deviceId	string	Yes	ID of the device to which the KVStoreResultSet object belongs.
query	Query	Yes	Query object to match.

Return value

Type	Description
Promise<KVStoreResultSet>	Promise used to return the KVStoreResultSet object that matches the specified device ID and Query object.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100001	Over max limits.
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
  let resultSet: distributedKVStore.KVStoreResultSet = xxx;
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_string_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.STRING,
        value: 'batch_test_string_value'
      }
    }
    entries.push(entry);
  }
  kvStore.putBatch(entries).then(async () => {
    console.info('Succeeded in putting batch');
  }).catch((err: BusinessError) => {
    console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
  });
  const query = new distributedKVStore.Query();
  query.prefixKey("batch_test");
  kvStore.getResultSet('localDeviceId', query).then((result) => {
    console.info('Succeeded in getting resultSet');
    resultSet = result;
  }).catch((err: BusinessError) => {
    console.error(`Failed to get resultSet.code is ${err.code},message is ${err.message}`);
  });
  query.deviceId('localDeviceId');
  console.info("GetResultSet " + query.getSqlLike());
  kvStore.closeResultSet(resultSet).then(() => {
    console.info('Succeeded in closing resultSet');
  }).catch((err: BusinessError) => {
    console.error(`Failed to close resultSet.code is ${err.code},message is ${err.message}`);
  });

} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to get resultSet.code is ${error.code},message is ${error.message}`);
}

getResultSet

getResultSet(query: Query): Promise<KVStoreResultSet>

Obtains a KVStoreResultSet object that matches the specified Query object for this device. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
query	Query	Yes	Query object to match.

Return value

Type	Description
Promise<KVStoreResultSet>	Promise used to return the KVStoreResultSet object obtained.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100001	Over max limits.
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
  let resultSet: distributedKVStore.KVStoreResultSet = xxx;
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_string_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.STRING,
        value: 'batch_test_string_value'
      }
    }
    entries.push(entry);
  }
  kvStore.putBatch(entries).then(async () => {
    console.info('Succeeded in putting batch');
  }).catch((err: BusinessError) => {
    console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
  });
  const query = new distributedKVStore.Query();
  query.prefixKey("batch_test");
  kvStore.getResultSet(query).then((result) => {
    console.info('Succeeded in getting result set');
    resultSet = result;
  }).catch((err: BusinessError) => {
    console.error(`Failed to get resultset.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}

getResultSet

getResultSet(query: Query, callback:AsyncCallback<KVStoreResultSet>): void

Obtains a KVStoreResultSet object that matches the specified Query object for this device. This API uses an asynchronous callback to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
query	Query	Yes	Query object to match.
callback	AsyncCallback<KVStoreResultSet>	Yes	Callback invoked to return the KVStoreResultSet object obtained.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100001	Over max limits.
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
  let resultSet: distributedKVStore.KVStoreResultSet = xxx;
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_string_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.STRING,
        value: 'batch_test_string_value'
      }
    }
    entries.push(entry);
  }
  kvStore.putBatch(entries, async (err) => {
    if (err != undefined) {
      console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in putting batch');
    const query = new distributedKVStore.Query();
    query.prefixKey("batch_test");
    kvStore.getResultSet(query, async (err, result) => {
      if (err != undefined) {
        console.error(`Failed to get resultSet.code is ${err.code},message is ${err.message}`);
        return;
      }
      console.info('Succeeded in getting resultSet');
      resultSet = result;
      kvStore.closeResultSet(resultSet, (err) => {
        if (err != undefined) {
          console.error(`Failed to close resultSet.code is ${err.code},message is ${err.message}`);
          return;
        }
        console.info('Succeeded in closing resultSet');
      })
    });
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to get resultSet.code is ${error.code},message is ${error.message}`);
}

getResultSet

getResultSet(predicates: dataSharePredicates.DataSharePredicates, callback: AsyncCallback<KVStoreResultSet>): void

Obtains a KVStoreResultSet object that matches the specified predicate object for this device. This API uses an asynchronous callback to return the result.

Model restriction: This API can be used only in the stage model.

System API: This is a system API.

System capability: SystemCapability.DistributedDataManager.DataShare.Provider

Parameters

Name	Type	Mandatory	Description
predicates	dataSharePredicates.DataSharePredicates	Yes	DataSharePredicates object that specifies the KVStoreResultSet object to obtain. If this parameter is null, define the processing logic.
callback	AsyncCallback<KVStoreResultSet>	Yes	Callback invoked to return the KVStoreResultSet object obtained.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100001	Over max limits.
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import dataSharePredicates from '@ohos.data.dataSharePredicates';
import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
  let resultSet: distributedKVStore.KVStoreResultSet = xxx;
  let predicates = new dataSharePredicates.DataSharePredicates();
  predicates.prefixKey("batch_test_string_key");
  kvStore.getResultSet(predicates, async (err, result) => {
    if (err != undefined) {
      console.error(`Failed to get resultset.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in getting result set');
    resultSet = result;
    kvStore.closeResultSet(resultSet, (err) => {
      if (err != undefined) {
        console.error(`Failed to close resultset.code is ${err.code},message is ${err.message}`);
        return;
      }
      console.info('Succeeded in closing result set');
    })
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}

getResultSet

getResultSet(predicates: dataSharePredicates.DataSharePredicates): Promise<KVStoreResultSet>

Obtains a KVStoreResultSet object that matches the specified predicate object for this device. This API uses a promise to return the result.

Model restriction: This API can be used only in the stage model.

System API: This is a system API.

System capability: SystemCapability.DistributedDataManager.DataShare.Provider

Parameters

Name	Type	Mandatory	Description
predicates	dataSharePredicates.DataSharePredicates	Yes	DataSharePredicates object that specifies the KVStoreResultSet object to obtain. If this parameter is null, define the processing logic.

Return value

Type	Description
Promise<KVStoreResultSet>	Promise that returns no value.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100001	Over max limits.
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import dataSharePredicates from '@ohos.data.dataSharePredicates';
import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
  let resultSet: distributedKVStore.KVStoreResultSet = xxx;
  let predicates = new dataSharePredicates.DataSharePredicates();
  predicates.prefixKey("batch_test_string_key");
  kvStore.getResultSet(predicates).then((result) => {
    console.info('Succeeded in getting result set');
    resultSet = result;
  }).catch((err: BusinessError) => {
    console.error(`Failed to get resultset.code is ${err.code},message is ${err.message}`);
  });
  kvStore.closeResultSet(resultSet).then(() => {
    console.info('Succeeded in closing result set');
  }).catch((err: BusinessError) => {
    console.error(`Failed to close resultset.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}

getResultSet

getResultSet(deviceId: string, predicates: dataSharePredicates.DataSharePredicates, callback: AsyncCallback<KVStoreResultSet>): void

Obtains a KVStoreResultSet object that matches the specified predicate object and device ID. This API uses an asynchronous callback to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().

Model restriction: This API can be used only in the stage model.

System API: This is a system API.

System capability: SystemCapability.DistributedDataManager.DataShare.Provider

Parameters

Name	Type	Mandatory	Description
deviceId	string	Yes	ID of the target device.
predicates	dataSharePredicates.DataSharePredicates	Yes	DataSharePredicates object that specifies the KVStoreResultSet object to obtain. If this parameter is null, define the processing logic.
callback	AsyncCallback<KVStoreResultSet>	Yes	Callback invoked to return the KVStoreResultSet object obtained.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100001	Over max limits.
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import dataSharePredicates from '@ohos.data.dataSharePredicates';
import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
  let resultSet: distributedKVStore.KVStoreResultSet = xxx;
  let predicates = new dataSharePredicates.DataSharePredicates();
  predicates.prefixKey("batch_test_string_key");
  kvStore.getResultSet('localDeviceId', predicates, async (err, result) => {
    if (err != undefined) {
      console.error(`Failed to get resultset.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in getting result set');
    resultSet = result;
    kvStore.closeResultSet(resultSet, (err) => {
      if (err != undefined) {
        console.error(`Failed to close resultset.code is ${err.code},message is ${err.message}`);
        return;
      }
      console.info('Succeeded in closing result set');
    })
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}

getResultSet

getResultSet(deviceId: string, predicates: dataSharePredicates.DataSharePredicates): Promise<KVStoreResultSet>

Obtains a KVStoreResultSet object that matches the specified predicate object and device ID. This API uses a promise to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().

Model restriction: This API can be used only in the stage model.

System API: This is a system API.

System capability: SystemCapability.DistributedDataManager.DataShare.Provider

Parameters

Name	Type	Mandatory	Description
deviceId	string	Yes	ID of the target device.
predicates	dataSharePredicates.DataSharePredicates	Yes	DataSharePredicates object that specifies the KVStoreResultSet object to obtain. If this parameter is null, define the processing logic.

Return value

Type	Description
Promise<KVStoreResultSet>	Promise that returns no value.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100001	Over max limits.
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import dataSharePredicates from '@ohos.data.dataSharePredicates';
import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
  let resultSet: distributedKVStore.KVStoreResultSet = xxx;
  let predicates = new dataSharePredicates.DataSharePredicates();
  predicates.prefixKey("batch_test_string_key");
  kvStore.getResultSet('localDeviceId', predicates).then((result) => {
    console.info('Succeeded in getting result set');
    resultSet = result;
  }).catch((err: BusinessError) => {
    console.error(`Failed to get resultset.code is ${err.code},message is ${err.message}`);
  });
  kvStore.closeResultSet(resultSet).then(() => {
    console.info('Succeeded in closing result set');
  }).catch((err: BusinessError) => {
    console.error(`Failed to close resultset.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}

getResultSize

getResultSize(query: Query, callback: AsyncCallback<number>): void

Obtains the number of results that match the specified Query object for this device. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
query	Query	Yes	Query object to match.
callback	AsyncCallback<number>	Yes	Callback invoked to return the number of results obtained.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_string_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.STRING,
        value: 'batch_test_string_value'
      }
    }
    entries.push(entry);
  }
  kvStore.putBatch(entries, async (err) => {
    console.info('Succeeded in putting batch');
    const query = new distributedKVStore.Query();
    query.prefixKey("batch_test");
    kvStore.getResultSize(query, async (err, resultSize) => {
      if (err != undefined) {
        console.error(`Failed to get result size.code is ${err.code},message is ${err.message}`);
        return;
      }
      console.info('Succeeded in getting result set size');
    });
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}

getResultSize

getResultSize(query: Query): Promise<number>

Obtains the number of results that match the specified Query object for this device. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Name	Type	Mandatory	Description
query	Query	Yes	Query object to match.

Return value

Type	Description
Promise<number>	Promise used to return the number of results obtained.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_string_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.STRING,
        value: 'batch_test_string_value'
      }
    }
    entries.push(entry);
  }
  kvStore.putBatch(entries).then(async () => {
    console.info('Succeeded in putting batch');
  }).catch((err: BusinessError) => {
    console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
  });
  const query = new distributedKVStore.Query();
  query.prefixKey("batch_test");
  kvStore.getResultSize(query).then((resultSize) => {
    console.info('Succeeded in getting result set size');
  }).catch((err: BusinessError) => {
    console.error(`Failed to get result size.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`An unexpected error occurred.code is ${error.code},message is ${error.code}`);
}

getResultSize

getResultSize(deviceId: string, query: Query, callback: AsyncCallback<number>): void;

Obtains the number of results that matches the specified device ID and Query object. This API uses an asynchronous callback to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Name	Type	Mandatory	Description
deviceId	string	Yes	ID of the device to which the KVStoreResultSet object belongs.
query	Query	Yes	Query object to match.
callback	AsyncCallback<number>	Yes	Callback invoked to return the number of results obtained.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_string_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.STRING,
        value: 'batch_test_string_value'
      }
    }
    entries.push(entry);
  }
  kvStore.putBatch(entries, async (err) => {
    if (err != undefined) {
      console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in putting batch');
    const query = new distributedKVStore.Query();
    query.prefixKey("batch_test");
    kvStore.getResultSize('localDeviceId', query, async (err, resultSize) => {
      if (err != undefined) {
        console.error(`Failed to get resultSize.code is ${err.code},message is ${err.message}`);
        return;
      }
      console.info('Succeeded in getting resultSize');
    });
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to get resultSize.code is ${error.code},message is ${error.message}`);
}

getResultSize

getResultSize(deviceId: string, query: Query): Promise<number>

Obtains the number of results that matches the specified device ID and Query object. This API uses a promise to return the result. > NOTE > > deviceId can be obtained by deviceManager.getAvailableDeviceListSync. > For details about how to obtain deviceId, see sync().

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Name	Type	Mandatory	Description
deviceId	string	Yes	ID of the device to which the KVStoreResultSet object belongs.
query	Query	Yes	Query object to match.

Return value

Type	Description
Promise<number>	Promise used to return the number of results obtained.

Error codes

For details about the error codes, see Distributed KV Store Error Codes.

ID	Error Message
15100003	Database corrupted.
15100005	Database or result set already closed.

Example

import { BusinessError } from '@ohos.base';

let kvStore: distributedKVStore.DeviceKVStore = xxx;
try {
  let entries: distributedKVStore.Entry[] = [];
  for (let i = 0; i < 10; i++) {
    let key = 'batch_test_string_key';
    let entry: distributedKVStore.Entry = {
      key: key + i,
      value: {
        type: distributedKVStore.ValueType.STRING,
        value: 'batch_test_string_value'
      }
    }
    entries.push(entry);
  }
  kvStore.putBatch(entries).then(async () => {
    console.info('Succeeded in putting batch');
  }).catch((err: BusinessError) => {
    console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
  });
  let query = new distributedKVStore.Query();
  query.prefixKey("batch_test");
  kvStore.getResultSize('localDeviceId', query).then((resultSize) => {
    console.info('Succeeded in getting resultSize');
  }).catch((err: BusinessError) => {
    console.error(`Failed to get resultSize.code is ${err.code},message is ${err.message}`);
  });
} catch (e) {
  let error = e as BusinessError;
  console.error(`Failed to get resultSize.code is ${error.code},message is ${error.message}`);
}

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