resultSet

A result set is a set of results returned after the relational database (RDB) query APIs are called. You can use the resultset APIs to obtain required data.

NOTE

The initial APIs of this module are supported since API version 7. Newly added APIs will be marked with a superscript to indicate their earliest API version.

The APIs of this module are no longer maintained since API version 9. You are advised to use @ohos.data.relationalStore#ResultSet.

ResultSet

Provides methods to access the result set, which is obtained by querying the RDB store.

Usage

You need to obtain a resultSet object by using RdbStore.query().

import dataRdb from '@ohos.data.rdb';
let predicates = new dataRdb.RdbPredicates("EMPLOYEE");
predicates.equalTo("AGE", 18);
let promise = rdbStore.query(predicates, ["ID", "NAME", "AGE", "SALARY", "CODES"]);
promise.then((resultSet) => {
    console.log(TAG + "resultSet columnNames:" + resultSet.columnNames);
    console.log(TAG + "resultSet columnCount:" + resultSet.columnCount);
});

Attributes

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

getColumnIndex

getColumnIndex(columnName: string): number

Obtains the column index based on the column name.

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

Parameters

Return value

Example

  resultSet.goToFirstRow();
  const id = resultSet.getLong(resultSet.getColumnIndex("ID"));
  const name = resultSet.getString(resultSet.getColumnIndex("NAME"));
  const age = resultSet.getLong(resultSet.getColumnIndex("AGE"));
  const salary = resultSet.getDouble(resultSet.getColumnIndex("SALARY"));

getColumnName

getColumnName(columnIndex: number): string

Obtains the column name based on the column index.

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

Parameters

Return value

Example

  const id = resultSet.getColumnName(0);
  const name = resultSet.getColumnName(1);
  const age = resultSet.getColumnName(2);

goTo

goTo(offset:number): boolean

Moves the cursor to the row based on the specified offset.

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

Parameters

Return value

Example

  let predicatesgoto = new dataRdb.RdbPredicates("EMPLOYEE");
  let promisequerygoto = rdbStore.query(predicatesgoto, ["ID", "NAME", "AGE", "SALARY", "CODES"]);
  promisequerygoto.then((resultSet) => {
      resultSet.goTo(1);
      resultSet.close();
  }).catch((err) => {
      console.log('query failed');
  });

goToRow

goToRow(position: number): boolean

Moves the cursor to the specified row in the result set.

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

Parameters

Return value

Example

  let predicatesgotorow = new dataRdb.RdbPredicates("EMPLOYEE");
  let promisequerygotorow = rdbStore.query(predicatesgotorow, ["ID", "NAME", "AGE", "SALARY", "CODES"]);
  promisequerygotorow.then((resultSet) => {
      resultSet.goToRow(5);
      resultSet.close();
  }).catch((err) => {
      console.log('query failed');
  });

goToFirstRow

goToFirstRow(): boolean

Moves the cursor to the first row of the result set.

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

Return value

Example

  let predicatesgoFirst = new dataRdb.RdbPredicates("EMPLOYEE");
  let promisequerygoFirst = rdbStore.query(predicatesgoFirst, ["ID", "NAME", "AGE", "SALARY", "CODES"]);
  promisequerygoFirst.then((resultSet) => {
      resultSet.goToFirstRow();
      resultSet.close();
  }).catch((err) => {
      console.log('query failed');
  });

goToLastRow

goToLastRow(): boolean

Moves the cursor to the last row of the result set.

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

Return value

Example

  let predicatesgoLast = new dataRdb.RdbPredicates("EMPLOYEE");
  let promisequerygoLast = rdbStore.query(predicatesgoLast, ["ID", "NAME", "AGE", "SALARY", "CODES"]);
  promisequerygoLast.then((resultSet) => {
      resultSet.goToLastRow();
      resultSet.close();
  }).catch((err) => {
      console.log('query failed');
  });

goToNextRow

goToNextRow(): boolean

Moves the cursor to the next row in the result set.

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

Return value

Example

  let predicatesgoNext = new dataRdb.RdbPredicates("EMPLOYEE");
  let promisequerygoNext = rdbStore.query(predicatesgoNext, ["ID", "NAME", "AGE", "SALARY", "CODES"]);
  promisequerygoNext.then((resultSet) => {
      resultSet.goToNextRow();
      resultSet.close();
  }).catch((err) => {
      console.log('query failed');
  });

goToPreviousRow

goToPreviousRow(): boolean

Moves the cursor to the previous row in the result set.

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

Return value

Example

  let predicatesgoPrev = new dataRdb.RdbPredicates("EMPLOYEE");
  let promisequerygoPrev = rdbStore.query(predicatesgoPrev, ["ID", "NAME", "AGE", "SALARY", "CODES"]);
  promisequerygoPrev.then((resultSet) => {
      resultSet.goToPreviousRow();
      resultSet.close();
  }).catch((err) => {
      console.log('query failed');
  });

getBlob

getBlob(columnIndex: number): Uint8Array

Obtains the value in the specified column in the current row as a byte array.

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

Parameters

Return value

Example

  const codes = resultSet.getBlob(resultSet.getColumnIndex("CODES"));

getString

getString(columnIndex: number): string

Obtains the value in the specified column in the current row as a string.

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

Parameters

Return value

Example

  const name = resultSet.getString(resultSet.getColumnIndex("NAME"));

getLong

getLong(columnIndex: number): number

Obtains the value in the specified column in the current row as a Long integer.

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

Parameters

Return value

Example

  const age = resultSet.getLong(resultSet.getColumnIndex("AGE"));

getDouble

getDouble(columnIndex: number): number

Obtains the value in the specified column in the current row as a double.

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

Parameters

Return value

Example

  const salary = resultSet.getDouble(resultSet.getColumnIndex("SALARY"));

isColumnNull

isColumnNull(columnIndex: number): boolean

Checks whether the value in the specified column of the current row is null.

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

Parameters

Return value

Example

  const isColumnNull = resultSet.isColumnNull(resultSet.getColumnIndex("CODES"));

close

close(): void

Closes this result set.

System capability: SystemCapability.DistributedDataManager.RelationalStore.Core

Example

  let predicatesClose = new dataRdb.RdbPredicates("EMPLOYEE");
  let promiseClose = rdbStore.query(predicatesClose, ["ID", "NAME", "AGE", "SALARY", "CODES"]);
  promiseClose.then((resultSet) => {
      resultSet.close();
  }).catch((err) => {
      console.log('Failed to close the resultset');
  });

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