@ohos.data.distributedKVStore (分布式键值数据库)

分布式键值数据库为应用程序提供不同设备间数据库的分布式协同能力。通过调用分布式键值数据库各个接口，应用程序可将数据保存到分布式键值数据库中，并可对分布式键值数据库中的数据进行增加、删除、修改、查询、同步等操作。

该模块提供以下分布式键值数据库相关的常用功能：

• KVManager：分布式键值数据库管理实例，用于获取数据库的相关信息。
• KVStoreResultSet：提供获取数据库结果集的相关方法，包括查询和移动数据读取位置等。
• Query：使用谓词表示数据库查询，提供创建Query实例、查询数据库中的数据和添加谓词的方法。
• SingleKVStore：单版本分布式键值数据库，不对数据所属设备进行区分，提供查询数据和同步数据的方法。
• DeviceKVStore：设备协同数据库，继承自SingleKVStore，以设备维度对数据进行区分，提供查询数据和同步数据的方法。

说明：

本模块首批接口从API version 9开始支持。后续版本的新增接口，采用上角标单独标记接口的起始版本。

导入模块

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

KVManagerConfig

提供KVManager实例的配置信息，包括调用方的包名和应用的上下文。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

Constants

分布式键值数据库常量。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

ValueType

数据类型枚举。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

Value

存储在数据库中的值对象。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

Entry

存储在数据库中的键值对。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

ChangeNotification

数据变更时通知的对象，包括数据插入的数据、更新的数据、删除的数据和设备ID。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

SyncMode

同步模式枚举。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

SubscribeType

订阅类型枚举。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

KVStoreType

分布式键值数据库类型枚举。

SecurityLevel

数据库的安全级别枚举。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

Options

用于提供创建数据库的配置信息。

Schema

表示数据库模式，可以在创建或打开数据库时创建Schema对象并将它们放入Options中。

系统能力： SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

STRICT：意味着严格模式，在此模式用户插入的Value格式与Schema定义必须严格匹配，字段不能多也不能少，如果不匹配则插入数据时数据库会返回错误。

COMPATIBLE：选择为COMPATIBLE模式则数据库检查Value格式时比较宽松，只需要Value具有Schema描述的特征即可，允许有多出的字段，例如：定义了id、name字段可以插入id、name、age等多个字段。

constructor

constructor()

用于创建Schema实例的构造函数。

系统能力： SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

示例：

let child1 = new distributedKVStore.FieldNode('id');
child1.type = distributedKVStore.ValueType.INTEGER;
child1.nullable = false;
child1.default = '1';
let child2 = new distributedKVStore.FieldNode('name');
child2.type = distributedKVStore.ValueType.STRING;
child2.nullable = false;
child2.default = 'zhangsan';

let schema = new distributedKVStore.Schema();
schema.root.appendChild(child1);
schema.root.appendChild(child2);
schema.indexes = ['$.id', '$.name'];
schema.mode = 1;
schema.skip = 0;

FieldNode

表示 Schema 实例的节点，提供定义存储在数据库中的值的方法。

系统能力： SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

constructor

constructor(name: string)

用于创建带有string字段FieldNode实例的构造函数。

系统能力： SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

参数：

appendChild

appendChild(child: FieldNode): boolean

在当前 FieldNode 中添加一个子节点。

系统能力： SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

参数：

返回值：

示例：

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

创建一个KVManager对象实例，用于管理数据库对象。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

示例：

Stage模型下的示例：

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模型下的示例：

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

分布式键值数据库管理实例，用于获取分布式键值数据库的相关信息。在调用KVManager的方法前，需要先通过createKVManager构建一个KVManager实例。

getKVStore

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

通过指定Options和storeId，创建并获取分布式键值数据库，使用callback异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

示例：

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

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: BusinessError, 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>

通过指定Options和storeId，创建并获取分布式键值数据库，使用Promise异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

示例：

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

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

通过storeId的值关闭指定的分布式键值数据库，使用callback异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

示例：

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

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: BusinessError, 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: BusinessError)=> {
      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>

通过storeId的值关闭指定的分布式键值数据库，使用Promise异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

示例：

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

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

通过storeId的值删除指定的分布式键值数据库，使用callback异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

示例：

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

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: BusinessError, 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: BusinessError) => {
      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>

通过storeId的值删除指定的分布式键值数据库，使用Promise异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

示例：

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

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

获取所有通过getKVStore方法创建的且没有调用deleteKVStore方法删除的分布式键值数据库的storeId，使用callback异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

示例：

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

try {
  kvManager.getAllKVStoreId('appId', (err: BusinessError, data: string[]) => {
    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[]>

获取所有通过getKVStore方法创建的且没有调用deleteKVStore方法删除的分布式键值数据库的storeId，使用Promise异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

示例：

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

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

订阅服务状态变更通知。如果服务终止，需要重新注册数据变更通知和同步完成事件回调通知，并且同步操作会返回失败。

系统能力： SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

参数：

示例：

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

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

取消订阅服务状态变更通知。参数中的deathCallback必须是已经订阅过的deathCallback，否则会取消订阅失败。

系统能力： SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

参数：

示例：

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

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

提供获取数据库结果集的相关方法，包括查询和移动数据读取位置等。同时允许打开的结果集的最大数量为8个。

在调用KVStoreResultSet的方法前，需要先通过getKVStore构建一个SingleKVStore或者DeviceKVStore实例。

getCount

getCount(): number

获取结果集中的总行数。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

返回值：

示例：

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

try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  let count: number;
  kvStore.getResultSet('batch_test_string_key').then((result: distributedKVStore.KVStoreResultSet) => {
    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

获取结果集中当前的读取位置。读取位置会因moveToFirst、moveToLast等操作而发生变化。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

返回值：

示例：

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

try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  let position: number;
  kvStore.getResultSet('batch_test_string_key').then((result: distributedKVStore.KVStoreResultSet) => {
    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

将读取位置移动到第一行。如果结果集为空，则返回false。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

返回值：

示例：

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

try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  let moved: boolean;
  kvStore.getResultSet('batch_test_string_key').then((result: distributedKVStore.KVStoreResultSet) => {
    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

将读取位置移动到最后一行。如果结果集为空，则返回false。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

返回值：

示例：

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

try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  let moved: boolean;
  kvStore.getResultSet('batch_test_string_key').then((result: distributedKVStore.KVStoreResultSet) => {
    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

将读取位置移动到下一行。如果结果集为空，则返回false。适用于全量获取数据库结果集的场景。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

返回值：

示例：

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

try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  let moved: boolean;
  kvStore.getResultSet('batch_test_string_key').then((result: distributedKVStore.KVStoreResultSet) => {
    console.info('getResultSet succeed.');
    resultSet = result;
    do {
      moved = resultSet.moveToNext();
      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

将读取位置移动到上一行。如果结果集为空，则返回false。适用于全量获取数据库结果集的场景。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

返回值：

示例：

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

try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  let moved: boolean;
  kvStore.getResultSet('batch_test_string_key').then((result: distributedKVStore.KVStoreResultSet) => {
    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

将读取位置移动到当前位置的相对偏移量。即当前游标位置向下偏移 offset 行。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

示例：

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

try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  let moved: boolean;
  kvStore.getResultSet('batch_test_string_key').then((result: distributedKVStore.KVStoreResultSet) => {
    console.info('Succeeded in getting resultSet');
    resultSet = result;
    moved = resultSet.move(2); //若当前位置为0，将读取位置从绝对位置为0的位置移动2行，即移动到绝对位置为2，行数为3的位置
    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

将读取位置从 0 移动到绝对位置。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

示例

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

try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  let moved: boolean;
  kvStore.getResultSet('batch_test_string_key').then((result: distributedKVStore.KVStoreResultSet) => {
    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

检查读取位置是否为第一行。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

返回值：

示例：

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

try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  let isfirst: boolean;
  kvStore.getResultSet('batch_test_string_key').then((result: distributedKVStore.KVStoreResultSet) => {
    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

检查读取位置是否为最后一行。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

返回值：

示例：

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

try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  let islast: boolean;
  kvStore.getResultSet('batch_test_string_key').then((result: distributedKVStore.KVStoreResultSet) => {
    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

检查读取位置是否在第一行之前。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

返回值：

示例：

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

try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  kvStore.getResultSet('batch_test_string_key').then((result: distributedKVStore.KVStoreResultSet) => {
    console.info('getResultSet succeed.');
    resultSet = result;
    let 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

检查读取位置是否在最后一行之后。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

返回值：

示例：

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

try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  kvStore.getResultSet('batch_test_string_key').then((result: distributedKVStore.KVStoreResultSet) => {
    console.info('getResultSet succeed.');
    resultSet = result;
    let 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

从当前位置获取对应的键值对。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

返回值：

示例：

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

try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  kvStore.getResultSet('batch_test_string_key').then((result: distributedKVStore.KVStoreResultSet) => {
    console.info('getResultSet succeed.');
    resultSet = result;
    let 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

使用谓词表示数据库查询，提供创建Query实例、查询数据库中的数据和添加谓词的方法。一个Query对象中谓词数量上限为256个。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

constructor

constructor()

用于创建Query实例的构造函数。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

reset

reset(): Query

重置Query对象。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

返回值：

示例：

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

构造一个Query对象来查询具有指定字段的条目，其值等于指定的值。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

示例：

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

构造一个Query对象以查询具有指定字段且值不等于指定值的条目。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

示例：

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

构造一个Query对象以查询具有大于指定值的指定字段的条目。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

示例：

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

构造一个Query对象以查询具有小于指定值的指定字段的条目。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

示例：

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

构造一个Query对象以查询具有指定字段且值大于或等于指定值的条目。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

示例：

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

构造一个Query对象以查询具有指定字段且值小于或等于指定值的条目。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

示例：

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

构造一个Query对象以查询具有值为null的指定字段的条目。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

示例：

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

构造一个Query对象以查询具有指定字段的条目，其值在指定的值列表中。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

示例：

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

构造一个Query对象以查询具有指定字段的条目，其值在指定的字符串值列表中。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

示例：

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

构造一个Query对象以查询具有指定字段的条目，该字段的值不在指定的值列表中。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

示例：

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

构造一个Query对象以查询具有指定字段且值不在指定字符串值列表中的条目。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

示例：

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

构造一个Query对象以查询具有与指定字符串值相似的指定字段的条目。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

示例：

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

构造一个Query对象以查询具有与指定字符串值不相似的指定字段的条目。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

示例：

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

构造一个带有与条件的查询对象。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

返回值：

示例：

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

构造一个带有或条件的Query对象。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

返回值：

示例：

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

构造一个Query对象，将查询结果按升序排序。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

示例：

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

构造一个Query对象，将查询结果按降序排序。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

示例：

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

构造一个Query对象来指定结果的数量和开始位置。该接口必须要在Query对象查询和升降序等操作之后调用，调用limit接口后，不可再对Query对象进行查询和升降序等操作。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

示例：

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

构造一个Query对象以查询具有值不为null的指定字段的条目。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

示例：

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

创建一个带有左括号的查询条件组。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

返回值：

示例：

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

创建一个带有右括号的查询条件组。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

返回值：

示例：

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

创建具有指定键前缀的查询条件。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

示例：

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

设置一个指定的索引，将优先用于查询。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

示例：

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

添加设备ID作为key的前缀。

说明：

其中deviceId通过调用deviceManager.getAvailableDeviceListSync方法得到。 deviceId具体获取方式请参考sync接口示例

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

示例：

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

获取Query对象的查询语句。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

返回值：

示例：

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

SingleKVStore数据库实例，提供增加数据、删除数据和订阅数据变更、订阅数据同步完成的方法。

在调用SingleKVStore的方法前，需要先通过getKVStore构建一个SingleKVStore实例。

put

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

添加指定类型键值对到数据库，使用callback异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

以下错误码的详细介绍请参见关系型数据库错误码。

示例：

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

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: BusinessError) => {
    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>

添加指定类型键值对到数据库，使用Promise异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

以下错误码的详细介绍请参见关系型数据库错误码。

示例：

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

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

批量插入键值对到SingleKVStore数据库中，使用callback异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

以下错误码的详细介绍请参见关系型数据库错误码。

示例：

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

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: BusinessError) => {
    if (err != undefined) {
      console.error(`Failed to put Batch.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in putting Batch');
    if (kvStore != null) {
      kvStore.getEntries('batch_test_string_key', (err: BusinessError, entries: distributedKVStore.Entry[]) => {
        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]}`);
      });
    } else {
      console.error('KvStore is null'); //后续示例代码与此处保持一致
    }
  });
} 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>

批量插入键值对到SingleKVStore数据库中，使用Promise异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

以下错误码的详细介绍请参见关系型数据库错误码。

示例：

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

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');
    if (kvStore != null) {
      kvStore.getEntries('batch_test_string_key').then((entries: distributedKVStore.Entry[]) => {
        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} `);
}

delete

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

从数据库中删除指定键值的数据，使用callback异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

以下错误码的详细介绍请参见关系型数据库错误码。

示例：

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

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: BusinessError) => {
    if (err != undefined) {
      console.error(`Failed to put.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in putting');
    if (kvStore != null) {
      kvStore.delete(KEY_TEST_STRING_ELEMENT, (err: BusinessError) => {
        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>

从数据库中删除指定键值的数据，使用Promise异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

以下错误码的详细介绍请参见关系型数据库错误码。

示例：

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

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`);
    if (kvStore != null) {
      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}`);
}

deleteBatch

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

批量删除SingleKVStore数据库中的键值对，使用callback异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

以下错误码的详细介绍请参见关系型数据库错误码。

示例：

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

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: BusinessError) => {
    if (err != undefined) {
      console.error(`Failed to put Batch.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in putting Batch');
    if (kvStore != null) {
      kvStore.deleteBatch(keys, async (err: BusinessError) => {
        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>

批量删除SingleKVStore数据库中的键值对，使用Promise异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

以下错误码的详细介绍请参见关系型数据库错误码。

示例：

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

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');
    if (kvStore != null) {
      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

删除指定设备的数据，使用callback异步回调。

说明：

其中deviceId通过调用deviceManager.getAvailableDeviceListSync方法得到。 deviceId具体获取方式请参考sync接口示例

系统能力： SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

参数：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

示例：

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

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: BusinessError) => {
    console.info('Succeeded in putting data');
    const deviceid = 'no_exist_device_id';
    if (kvStore != null) {
      kvStore.removeDeviceData(deviceid, async (err: BusinessError) => {
        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} `);
          if (kvStore != null) {
            kvStore.get(KEY_TEST_STRING_ELEMENT, async (err: BusinessError, data: boolean | string | number | Uint8Array) => {
              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>

删除指定设备的数据，使用Promise异步回调。

说明：

其中deviceId通过调用deviceManager.getAvailableDeviceListSync方法得到。 deviceId具体获取方式请参考sync接口示例

系统能力： SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

参数：

返回值：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

示例：

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

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: boolean | string | number | Uint8Array) => {
    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

获取指定键的值，使用callback异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

示例：

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


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: BusinessError) => {
    if (err != undefined) {
      console.error(`Failed to put.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info("Succeeded in putting");
    if (kvStore != null) {
      kvStore.get(KEY_TEST_STRING_ELEMENT, (err: BusinessError, data: boolean | string | number | Uint8Array) => {
        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>

获取指定键的值，使用Promise异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

示例：

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


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`);
    if (kvStore != null) {
      kvStore.get(KEY_TEST_STRING_ELEMENT).then((data: boolean | string | number | Uint8Array) => {
        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

获取匹配指定键前缀的所有键值对，使用callback异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

示例：

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

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: BusinessError) => {
    if (err != undefined) {
      console.error(`Failed to put Batch.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in putting Batch');
    if (kvStore != null) {
      kvStore.getEntries('batch_test_string_key', (err: BusinessError, entries: distributedKVStore.Entry[]) => {
        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[]>

获取匹配指定键前缀的所有键值对，使用Promise异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

示例：

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


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');
    if (kvStore != null) {
      kvStore.getEntries('batch_test_string_key').then((entries: distributedKVStore.Entry[]) => {
        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

获取与指定Query对象匹配的键值对列表，使用callback异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

示例：

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

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: BusinessError) => {
    console.info('Succeeded in putting Batch');
    const query = new distributedKVStore.Query();
    query.prefixKey("batch_test");
    if (kvStore != null) {
      kvStore.getEntries(query, (err: BusinessError, entries: distributedKVStore.Entry[]) => {
        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[]>

获取与指定Query对象匹配的键值对列表，使用Promise异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

示例：

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

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");
    if (kvStore != null) {
      kvStore.getEntries(query).then((entries: distributedKVStore.Entry[]) => {
        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

从SingleKVStore数据库中获取具有指定前缀的结果集，使用callback异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

示例：

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

try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  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: BusinessError) => {
    if (err != undefined) {
      console.error(`Failed to put batch.code is ${err.code},message is ${err.message}`);
      return;
    }
    console.info('Succeeded in putting batch');
    if (kvStore != null) {
      kvStore.getResultSet('batch_test_string_key', async (err: BusinessError, result: distributedKVStore.KVStoreResultSet) => {
        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;
        if (kvStore != null) {
          kvStore.closeResultSet(resultSet, (err: BusinessError) => {
            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>

从SingleKVStore数据库中获取具有指定前缀的结果集，使用Promise异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

示例：

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

try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  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: distributedKVStore.KVStoreResultSet) => {
    console.info('Succeeded in getting result set');
    resultSet = result;
    if (kvStore != null) {
      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((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

获取与指定Query对象匹配的KVStoreResultSet对象，使用callback异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

示例：

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

try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  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: BusinessError) => {
    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");
    if (kvStore != null) {
      kvStore.getResultSet(query, async (err: BusinessError, result: distributedKVStore.KVStoreResultSet) => {
        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>

获取与指定Query对象匹配的KVStoreResultSet对象，使用Promise异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

示例：

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

try {
  let resultSet: distributedKVStore.KVStoreResultSet;
  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: distributedKVStore.KVStoreResultSet) => {
    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}`);
}

closeResultSet

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

关闭由SingleKvStore.getResultSet返回的KVStoreResultSet对象，使用callback异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

示例：

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

let resultSet: distributedKVStore.KVStoreResultSet;
try {
  kvStore.getResultSet('batch_test_string_key', async (err: BusinessError, result: distributedKVStore.KVStoreResultSet) => {
    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;
    if (kvStore != null) {
      kvStore.closeResultSet(resultSet, (err: BusinessError) => {
        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}`);
}

closeResultSet

closeResultSet(resultSet: KVStoreResultSet): Promise<void>

关闭由SingleKvStore.getResultSet返回的KVStoreResultSet对象，使用Promise异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

示例：

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

let resultSet: distributedKVStore.KVStoreResultSet;
try {
  kvStore.getResultSet('batch_test_string_key').then((result: distributedKVStore.KVStoreResultSet) => {
    console.info('Succeeded in getting result set');
    resultSet = result;
    if (kvStore != null) {
      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((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}`);
}

getResultSize

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

获取与指定Query对象匹配的结果数，使用callback异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

示例：

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

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: BusinessError) => {
    console.info('Succeeded in putting batch');
    const query = new distributedKVStore.Query();
    query.prefixKey("batch_test");
    if (kvStore != null) {
      kvStore.getResultSize(query, async (err: BusinessError, resultSize: number) => {
        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>

获取与指定Query对象匹配的结果数，使用Promise异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

示例：

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

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: number) => {
    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

以指定名称备份数据库，使用callback异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

示例：

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

let file = "BK001";
try {
  kvStore.backup(file, (err: BusinessError) => {
    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>

以指定名称备份数据库，使用Promise异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

示例：

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

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

从指定的数据库文件恢复数据库，使用callback异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

示例：

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

let file = "BK001";
try {
  kvStore.restore(file, (err: BusinessError) => {
    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>

从指定的数据库文件恢复数据库，使用Promise异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

示例：

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

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

根据指定名称删除备份文件，使用callback异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

示例：

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

let files = ["BK001", "BK002"];
try {
  kvStore.deleteBackup(files, (err: BusinessError, data: [string, number][]) => {
    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]>>

根据指定名称删除备份文件，使用Promise异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

示例：

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

let files = ["BK001", "BK002"];
try {
  kvStore.deleteBackup(files).then((data: [string, number][]) => {
    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

启动SingleKVStore数据库中的事务，使用callback异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

以下错误码的详细介绍请参见关系型数据库错误码。

示例：

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

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;
} //自定义函数，放置在作用域最外侧，防止语法检查报错

try {
  let count = 0;
  kvStore.on('dataChange', 0, (data: distributedKVStore.ChangeNotification) => {
    console.info(`startTransaction 0 ${data}`);
    count++;
  });
  kvStore.startTransaction(async (err: BusinessError) => {
    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}`);
    if (kvStore != null) {
      kvStore.putBatch(entries, async (err: BusinessError) => {
        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>

启动SingleKVStore数据库中的事务，使用Promise异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

返回值：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

以下错误码的详细介绍请参见关系型数据库错误码。

示例：

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

try {
  let count = 0;
  kvStore.on('dataChange', distributedKVStore.SubscribeType.SUBSCRIBE_TYPE_ALL, (data: distributedKVStore.ChangeNotification) => {
    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

提交SingleKVStore数据库中的事务，使用callback异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

示例：

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

try {
  kvStore.commit((err: BusinessError) => {
    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>

提交SingleKVStore数据库中的事务，使用Promise异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

返回值：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

示例：

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

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

在SingleKVStore数据库中回滚事务，使用callback异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

示例：

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

try {
  kvStore.rollback((err: BusinessError) => {
    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>

在SingleKVStore数据库中回滚事务，使用Promise异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

返回值：

错误码：

以下错误码的详细介绍请参见分布式键值数据库错误码。

示例：

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

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

设定是否开启同步，使用callback异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

示例：

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

try {
  kvStore.enableSync(true, (err: BusinessError) => {
    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>

设定是否开启同步，使用Promise异步回调。

系统能力： SystemCapability.DistributedDataManager.KVStore.Core

参数：

返回值：

示例：

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

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}`);
}