harmony 鸿蒙Distributed Data Management Changelog

2025-06-12
浏览 (35)

Distributed Data Management Changelog

cl.relationalStore.1 Change in the Return Value of getRow or getValue for an Empty Uint8Array

Access Level

Public API

Reason for Change

When an empty (zero-length) Uint8Array is inserted into a column of the BLOB type, null will be written to the database. When getRow() or getValue() is called, the value obtained does not match the value inserted.

Change Impact

This change is a non-compatible change.

Before the change:
If an empty Uint8Array is inserted into a column of the BLOB type, calling getRow/getValue will return null.

After the change:
If an empty Uint8Array is inserted into a column of the BLOB type, calling getRow/getValue will return an empty Uint8Array.

Start API Level

API	Start API Level
getRow	API 11
getValue	API 12

Change Since

OpenHarmony SDK 5.0.0.46

Key API/Component Changes

getRow in @ohos.data.relationalStore.d.ts. getValue in @ohos.data.relationalStore.d.ts.

Adaptation Guide

After the change, the interface invoking mode remains unchanged. The value returned by getRow() or getValue() changes.

import { relationalStore } from '@kit.ArkData';
import { BusinessError } from '@kit.BasicServicesKit';
import { UIAbility } from '@kit.AbilityKit';
import { window } from '@kit.ArkUI';

const STORE_CONFIG: relationalStore.StoreConfig = {
  name: "RdbTest.db",
  securityLevel: relationalStore.SecurityLevel.S3
};
const CREATE_TABLE_TEST =
  "CREATE TABLE IF NOT EXISTS EMPLOYEE (id INTEGER PRIMARY KEY AUTOINCREMENT,name TEXT NOT NULL, age INTEGER, salary REAL, blobType BLOB)";

let store: relationalStore.RdbStore|undefined = undefined;
relationalStore.getRdbStore(this.context, STORE_CONFIG, (err: BusinessError, rdbStore: relationalStore.RdbStore) => {
  store = rdbStore;
  store.executeSql(CREATE_TABLE_TEST);
  if (err) {
    console.error(`Get RdbStore failed, code is ${err.code},message is ${err.message}`);
    return;
  }
  console.info('Get RdbStore successfully.');
})
// Insert a Uint8Array whose length is 0 into ValuesBucket of the blob type, and obtain the data.
let resultSet: relationalStore.ResultSet|undefined = undefined;
let predicates = new relationalStore.RdbPredicates("EMPLOYEE");
if (store != undefined) {
  (store as relationalStore.RdbStore).query(predicates).then((result: relationalStore.ResultSet) => {
    resultSet = result;
  });
}
if (resultSet != undefined) {
  // blobType is the name of the column whose data type is blob.
  const codes = (resultSet as relationalStore.ResultSet).getValue((resultSet as relationalStore.ResultSet).getColumnIndex("blobType"));
}
// Before the change, the value of codes is null.
// After the change, the value of codes is an empty Uint8Array.

if (resultSet != undefined) {
  const row = (resultSet as relationalStore.ResultSet).getRow();
}
// Before the change, row.blobType is null.
// After the change, row.blobType is an empty Uint8Array.