Distributed Data Management

Distributed data management provides collaboration between databases of different devices for applications. The APIs provided by distributed data management can be used to save data to the distributed database and perform operations such as adding, deleting, modifying, and querying data in the distributed database.

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.

Modules to Import

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

distributedData.createKVManager

createKVManager(config: KVManagerConfig, callback: AsyncCallback<KVManager>): void

Creates a KVManager object to manage key-value (KV) stores. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Example

let kvManager;
try {
    const kvManagerConfig = {
        bundleName : 'com.example.datamanagertest',
        userInfo : {
            userId : '0',
            userType : distributedData.UserType.SAME_USER_ID
        }
    }
    distributedData.createKVManager(kvManagerConfig, function (err, manager) {
        if (err) {
            console.log("createKVManager err: "  + JSON.stringify(err));
            return;
        }
        console.log("createKVManager success");
        kvManager = manager;
    });
} catch (e) {
    console.log("An unexpected error occurred. Error:" + e);
}

distributedData.createKVManager

createKVManager(config: KVManagerConfig): Promise<KVManager>

Creates a KVManager object to manage KV stores. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Return value

Example

let kvManager;
try {
    const kvManagerConfig = {
        bundleName : 'com.example.datamanagertest',
        userInfo : {
            userId : '0',
            userType : distributedData.UserType.SAME_USER_ID
        }
    }
    distributedData.createKVManager(kvManagerConfig).then((manager) => {
        console.log("createKVManager success");
        kvManager = manager;
    }).catch((err) => {
        console.log("createKVManager err: "  + JSON.stringify(err));
    });
} catch (e) {
    console.log("An unexpected error occurred. Error:" + e);
}

KVManagerConfig

Provides configuration of the KVManager object, including the bundle name and user information of the caller.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

UserInfo

Defines user information.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

UserType

Defines the user type.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

KVManager

Creates a KVManager object to obtain KV store information. Before calling any method in KVManager, you must use createKVManager to create a KVManager object.

getKVStore

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

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Example

let kvStore;
let kvManager;
try {
    const options = {
        createIfMissing : true,
        encrypt : false,
        backup : false,
        autoSync : true,
        kvStoreType : distributedData.KVStoreType.SINGLE_VERSION,
        securityLevel : distributedData.SecurityLevel.S2,
    };
    kvManager.getKVStore('storeId', options, function (err, store) {
        if (err) {
            console.log("getKVStore err: "  + JSON.stringify(err));
            return;
        }
        console.log("getKVStore success");
        kvStore = store;
    });
} catch (e) {
    console.log("An unexpected error occurred. Error:" + e);
}

getKVStore

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

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Return value

Example

let kvStore;
let kvManager;
try {
    const options = {
        createIfMissing : true,
        encrypt : false,
        backup : false,
        autoSync : true,
        kvStoreType : distributedData.KVStoreType.SINGLE_VERSION,
        securityLevel : distributedData.SecurityLevel.S2,
    };
    kvManager.getKVStore('storeId', options).then((store) => {
        console.log("getKVStore success");
        kvStore = store;
    }).catch((err) => {
        console.log("getKVStore err: "  + JSON.stringify(err));
    });
} catch (e) {
    console.log("An unexpected error occurred. Error:" + e);
}

closeKVStore⁸⁺

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

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Example

let kvStore;
let kvManager;
const options = {
    createIfMissing : true,
    encrypt : false,
    backup : false,
    autoSync : true,
    kvStoreType : distributedData.KVStoreType.SINGLE_VERSION,
    schema : '',
    securityLevel : distributedData.SecurityLevel.S2,
 }
 try {
    kvManager.getKVStore('storeId', options, async function (err, store) {
    console.log('getKVStore success');
    kvStore = store;
    await kvManager.closeKVStore('appId', 'storeId', kvStore, function (err, data) {
        console.log('closeKVStore success');
    });
    });
} catch (e) {
    console.log('closeKVStore e ' + e);
}

closeKVStore⁸⁺

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

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Return value

Example

let kvManager;
let kvStore;
const options = {
    createIfMissing : true,
    encrypt : false,
    backup : false,
    autoSync : true,
    kvStoreType : distributedData.KVStoreType.SINGLE_VERSION,
    schema : '',
    securityLevel : distributedData.SecurityLevel.S2,
}
 try {
    kvManager.getKVStore('storeId', options).then(async (store) => {
    console.log('getKVStore success');
    kvStore = store;
    await kvManager.closeKVStore('appId', 'storeId', kvStore).then(() => {
        console.log('closeKVStore success');
    }).catch((err) => {
        console.log('closeKVStore err ' + JSON.stringify(err));
    });
    }).catch((err) => {
        console.log('CloseKVStore getKVStore err ' + JSON.stringify(err));
    });
 } catch (e) {
    console.log('closeKVStore e ' + e);
}  

deleteKVStore⁸⁺

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

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Example

let kvManager;
let kvStore;
const options = {
    createIfMissing : true,
    encrypt : false,
    backup : false,
    autoSync : true,
    kvStoreType : distributedData.KVStoreType.SINGLE_VERSION,
    schema : '',
    securityLevel : distributedData.SecurityLevel.S2,
}
try {
    kvManager.getKVStore('store', options, async function (err, store) {
        console.log('getKVStore success');
        kvStore = store;
        await kvManager.deleteKVStore('appId', 'storeId', function (err, data) {
            console.log('deleteKVStore success');
        });
    });
} catch (e) {
    console.log('DeleteKVStore e ' + e);
}

deleteKVStore⁸⁺

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

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Return value

Example

let kvManager;
let kvStore;
const options = {
    createIfMissing : true,
    encrypt : false,
    backup : false,
    autoSync : true,
    kvStoreType : distributedData.KVStoreType.SINGLE_VERSION,
    schema : '',
    securityLevel : distributedData.SecurityLevel.S2,
}
try {
    kvManager.getKVStore('storeId', options).then(async (store) => {
        console.log('getKVStore success');
        kvStore = store;
        await kvManager.deleteKVStore('appId', 'storeId').then(() => {
            console.log('deleteKVStore success');
        }).catch((err) => {
            console.log('deleteKVStore err ' + JSON.stringify(err));
        });
    }).catch((err) => {
        console.log('getKVStore err ' + JSON.stringify(err));
    });
} catch (e) {
    console.log('deleteKVStore e ' + e);
}

getAllKVStoreId⁸⁺

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

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Example

let kvManager;
try {
    kvManager.getAllKVStoreId('appId', function (err, data) {
        console.log('GetAllKVStoreId success');
        console.log('GetAllKVStoreId size = ' + data.length);
    });
} catch (e) {
    console.log('GetAllKVStoreId e ' + e);
}

getAllKVStoreId⁸⁺

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

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Return value

Example

let kvManager;
try {
    console.log('GetAllKVStoreId');
    kvManager.getAllKVStoreId('apppId').then((data) => {
        console.log('getAllKVStoreId success');
        console.log('size = ' + data.length);
    }).catch((err) => {
        console.log('getAllKVStoreId err ' + JSON.stringify(err));
    });
} catch(e) {
    console.log('getAllKVStoreId e ' + e);
}

on('distributedDataServiceDie')⁸⁺

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

Subscribes to the distributedDataServiceDie events. This API uses a synchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Example

let kvManager;
try {
    
    console.log('KVManagerOn');
    const deathCallback = function () {
        console.log('death callback call');
    }
    kvManager.on('distributedDataServiceDie', deathCallback);
} catch (e) {
    console.log("An unexpected error occurred. Error:" + e);
}

off('distributedDataServiceDie')⁸⁺

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

Unsubscribes from the distributedDataServiceDie events. This API uses a synchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Example

let kvManager;
try {
    console.log('KVManagerOff');
    const deathCallback = function () {
        console.log('death callback call');
    }
    kvManager.off('distributedDataServiceDie', deathCallback);
} catch (e) {
    console.log("An unexpected error occurred. Error:" + e);
}
    

Options

Provides KV store configuration.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

KVStoreType

Defines the KV store types.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

SecurityLevel

Defines the KV store security levels.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Constants

Defines the KV store constants.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Schema⁸⁺

Defines a database schema. When creating or opening a KV store, you can create a Schema object and put it into Options.

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

constructor⁸⁺

constructor()

A constructor used to create a Schema instance.

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

FieldNode⁸⁺

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

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

constructor⁸⁺

constructor(name: string)

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

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

appendChild⁸⁺

appendChild(child: FieldNode): boolean

Appends a child node to this FieldNode.

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Return value

Example

import ddm from '@ohos.data.distributedData';
try {
    let node = new ddm.FieldNode("root");
    let child1 = new ddm.FieldNode("child1");
    let child2 = new ddm.FieldNode("child2");
    let child3 = new ddm.FieldNode("child3");
    node.appendChild(child1);
    node.appendChild(child2);
    node.appendChild(child3);
    console.log("appendNode " + node.toJson());
    child1 = null;
    child2 = null;
    child3 = null;
    node = null;
} catch (e) {
    console.log("AppendChild " + e);
}

KvStoreResultSet⁸⁺

Provides methods to obtain the KV store result set and query or move the data read position. Before calling any method in KvStoreResultSet, you must use KvStore to create a KvStore instance.

getCount⁸⁺

getCount(): number

Obtains the number of rows in the result set.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Example

let kvStore;
try {
    let resultSet;
    kvStore.getResultSet('batch_test_string_key').then((result) => {
        console.log('getResultSet success');
        resultSet = result;
    }).catch((err) => {
        console.log('getResultSet fail ' + err);
    });
    const count = resultSet.getCount();
    console.log("GetCount " + count);
} catch (e) {
    console.log("GetCount fail " + e);
}

getPosition⁸⁺

getPosition(): number

Obtains the current data read position (position from which data is read) in the result set.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Example

let kvStore;
try {
    let resultSet;
    kvStore.getResultSet('batch_test_string_key').then((result) => {
        console.log('getResultSet success');
        resultSet = result;
    }).catch((err) => {
        console.log('getResultSet fail ' + err);
    });
    const position = resultSet.getPosition();
    console.log("getPosition " + position);
} catch (e) {
    console.log("GetPosition fail " + e);
}

moveToFirst⁸⁺

moveToFirst(): boolean

Moves the data read position to the first row.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Example

let kvStore;
try {
    let resultSet;
    kvStore.getResultSet('batch_test_string_key').then((result) => {
        console.log('getResultSet success');
        resultSet = result;
    }).catch((err) => {
        console.log('getResultSet fail ' + err);
    });
    const moved = resultSet.moveToFirst();
    console.log("moveToFirst " + moved);
} catch (e) {
    console.log("MoveToFirst fail " + e);
}

moveToLast⁸⁺

moveToLast(): boolean

Moves the data read position to the last row.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Example

let kvStore;
try {
    let resultSet;
    kvStore.getResultSet('batch_test_string_key').then((result) => {
        console.log('getResultSet success');
        resultSet = result;
    }).catch((err) => {
        console.log('getResultSet fail ' + err);
    });
    const moved = resultSet.moveToLast();
    console.log("moveToLast " + moved);
} catch (e) {
    console.log("moveToLast fail " + e);
}

moveToNext⁸⁺

moveToNext(): boolean

Moves the data read position to the next row.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Example

let kvStore;
try {
    let resultSet;
    kvStore.getResultSet('batch_test_string_key').then((result) => {
        console.log('getResultSet success');
        resultSet = result;
    }).catch((err) => {
        console.log('getResultSet fail ' + err);
    });
    const moved = resultSet.moveToNext();
    console.log("moveToNext " + moved);
} catch (e) {
    console.log("moveToNext fail " + e);
}

moveToPrevious⁸⁺

moveToPrevious(): boolean

Moves the data read position to the previous row.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Example

let kvStore;
try {
    let resultSet;
    kvStore.getResultSet('batch_test_string_key').then((result) => {
        console.log('getResultSet success');
        resultSet = result;
    }).catch((err) => {
        console.log('getResultSet fail ' + err);
    });
    const moved = resultSet.moveToPrevious();
    console.log("moveToPrevious " + moved);
} catch (e) {
    console.log("moveToPrevious fail " + e);
}

move⁸⁺

move(offset: number): boolean

Moves the data read position with the specified offset from the current position.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Return value

Example

let kvStore;
try {
    let resultSet;
    kvStore.getResultSet('batch_test_string_key').then((result) => {
        console.log('getResultSet success');
        resultSet = result;
    }).catch((err) => {
        console.log('getResultSet fail ' + err);
    });
    const moved = resultSet.move();
    console.log("move " + moved);
} catch (e) {
    console.log("move fail " + e);
}

moveToPosition⁸⁺

moveToPosition(position: number): boolean

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Return value

Example

let kvStore;
try {
    let resultSet;
    kvStore.getResultSet('batch_test_string_key').then((result) => {
        console.log('getResultSet success');
        resultSet = result;
    }).catch((err) => {
        console.log('getResultSet fail ' + err);
    });
    const moved = resultSet.moveToPosition();
    console.log("moveToPosition " + moved);
} catch (e) {
    console.log("moveToPosition fail " + e);
}

isFirst⁸⁺

isFirst(): boolean

Checks whether the data read position is the first row.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Example

let kvStore;
try {
    let resultSet;
    kvStore.getResultSet('batch_test_string_key').then((result) => {
        console.log('getResultSet success');
        resultSet = result;
    }).catch((err) => {
        console.log('getResultSet fail ' + err);
    });
    const moved = resultSet.isFirst();
    console.log("isFirst " + moved);
} catch (e) {
    console.log("isFirst fail " + e);
}

isLast⁸⁺

isLast(): boolean

Checks whether the data read position is the last row.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Example

let kvStore;
try {
    let resultSet;
    kvStore.getResultSet('batch_test_string_key').then((result) => {
        console.log('getResultSet success');
        resultSet = result;
    }).catch((err) => {
        console.log('getResultSet fail ' + err);
    });
    const moved = resultSet.isLast();
    console.log("isLast " + moved);
} catch (e) {
    console.log("isLast fail " + e);
}

isBeforeFirst⁸⁺

isBeforeFirst(): boolean

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Example

let kvStore;
try {
    let resultSet;
    kvStore.getResultSet('batch_test_string_key').then((result) => {
        console.log('getResultSet success');
        resultSet = result;
    }).catch((err) => {
        console.log('getResultSet fail ' + err);
    });
    const moved = resultSet.isBeforeFirst();
    console.log("isBeforeFirst " + moved);
} catch (e) {
    console.log("isBeforeFirst fail " + e);
}

isAfterLast⁸⁺

isAfterLast(): boolean

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Example

let kvStore;
try {
    let resultSet;
    kvStore.getResultSet('batch_test_string_key').then((result) => {
        console.log('getResultSet success');
        resultSet = result;
    }).catch((err) => {
        console.log('getResultSet fail ' + err);
    });
    const moved = resultSet.isAfterLast();
    console.log("isAfterLast " + moved);
} catch (e) {
    console.log("isAfterLast fail " + e);
}

getEntry⁸⁺

getEntry(): Entry

Obtains a KV pair.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Example

let kvStore;
try {
    let resultSet;
    kvStore.getResultSet('batch_test_string_key').then((result) => {
        console.log('getResultSet success');
        resultSet = result;
    }).catch((err) => {
        console.log('getResultSet fail ' + err);
    });
    const moved = resultSet.moveToNext();
    const entry  = resultSet.getEntry();
    console.log("getEntry " + JSON.stringify(entry));
} catch (e) {
    console.log("getEntry fail " + e);
}

Query⁸⁺

Provides methods to create a Query object, which defines different data query criteria.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

constructor⁸⁺

constructor()

A constructor used to create a Schema instance.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

reset⁸⁺

reset(): Query

Resets the Query object that contains common query options.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Example

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

equalTo⁸⁺

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

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Return value

Example

try {
    let query = new distributedData.Query();
    query.equalTo("field", "value");
    console.log("query is " + query.getSqlLike());
    query = null;
} catch (e) {
    console.log("dumplicated calls should be ok :" + e);
}

notEqualTo⁸⁺

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

Return value

Example

try {
    let query = new distributedData.Query();
    query.notEqualTo("field", "value");
    console.log("query is " + query.getSqlLike());
    query = null;
} catch (e) {
    console.log("dumplicated calls should be ok :" + e);
}

greaterThan⁸⁺

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

Return value

Example

try {
    let query = new distributedData.Query();
    query.greaterThan("field", "value");
    console.log("query is " + query.getSqlLike());
    query = null;
} catch (e) {
    console.log("dumplicated calls should be ok :" + e);
}

lessThan⁸⁺

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

Return value

Example

try {
    let query = new distributedData.Query();
    query.lessThan("field", "value");
    console.log("query is " + query.getSqlLike());
    query = null;
} catch (e) {
    console.log("dumplicated calls should be ok :" + e);
}

greaterThanOrEqualTo⁸⁺

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

Return value

Example

try {
    let query = new distributedData.Query();
    query.greaterThanOrEqualTo("field", "value");
    console.log("query is " + query.getSqlLike());
    query = null;
} catch (e) {
    console.log("dumplicated calls should be ok :" + e);
}

lessThanOrEqualTo⁸⁺

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

Return value

Example

try {
    let query = new distributedData.Query();
    query.lessThanOrEqualTo("field", "value");
    console.log("query is " + query.getSqlLike());
    query = null;
} catch (e) {
    console.log("dumplicated calls should be ok :" + e);
}

isNull⁸⁺

isNull(field: string): Query

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Return value

Example

try {
    let query = new distributedData.Query();
    query.isNull("field");
    console.log("query is " + query.getSqlLike());
    query = null;
} catch (e) {
    console.log("dumplicated calls should be ok :" + e);
}

inNumber⁸⁺

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

Return value

Example

try {
    let query = new distributedData.Query();
    query.inNumber("field", [0, 1]);
    console.log("query is " + query.getSqlLike());
    query = null;
} catch (e) {
    console.log("dumplicated calls should be ok :" + e);
}

inString⁸⁺

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

Return value

Example

try {
    let query = new distributedData.Query();
    query.inString("field", ['test1', 'test2']);
    console.log("query is " + query.getSqlLike());
    query = null;
} catch (e) {
    console.log("dumplicated calls should be ok :" + e);
}

notInNumber⁸⁺

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

Return value

Example

try {
    let query = new distributedData.Query();
    query.notInNumber("field", [0, 1]);
    console.log("query is " + query.getSqlLike());
    query = null;
} catch (e) {
    console.log("dumplicated calls should be ok :" + e);
}

notInString⁸⁺

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

Return value

Example

try {
    let query = new distributedData.Query();
    query.notInString("field", ['test1', 'test2']);
    console.log("query is " + query.getSqlLike());
    query = null;
} catch (e) {
    console.log("dumplicated calls should be ok :" + e);
}

like⁸⁺

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

Return value

Example

try {
    let query = new distributedData.Query();
    query.like("field", "value");
    console.log("query is " + query.getSqlLike());
    query = null;
} catch (e) {
    console.log("dumplicated calls should be ok :" + e);
}

unlike⁸⁺

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

Return value

Example

try {
    let query = new distributedData.Query();
    query.unlike("field", "value");
    console.log("query is " + query.getSqlLike());
    query = null;
} catch (e) {
    console.log("dumplicated calls should be ok :" + e);
}

and⁸⁺

and(): Query

Creates a Query object with the AND condition.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Example

try {
    let query = new distributedData.Query();
    query.notEqualTo("field", "value1");
    query.and();
    query.notEqualTo("field", "value2");
    console.log("query is " + query.getSqlLike());
    query = null;
} catch (e) {
    console.log("dumplicated calls should be ok :" + e);
}

or⁸⁺

or(): Query

Creates a Query object with the OR condition.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Example

try {
    let query = new distributedData.Query();
    query.notEqualTo("field", "value1");
    query.or();
    query.notEqualTo("field", "value2");
    console.log("query is " + query.getSqlLike());
    query = null;
} catch (e) {
    console.log("dumplicated calls should be ok :" + e);
}

orderByAsc⁸⁺

orderByAsc(field: string): Query

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Return value

Example

try {
    let query = new distributedData.Query();
    query.notEqualTo("field", "value");
    query.orderByAsc("field");
    console.log("query is " + query.getSqlLike());
    query = null;
} catch (e) {
    console.log("dumplicated calls should be ok :" + e);
}

orderByDesc⁸⁺

orderByDesc(field: string): Query

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Return value

Example

try {
    let query = new distributedData.Query();
    query.notEqualTo("field", "value");
    query.orderByDesc("field");
    console.log("query is " + query.getSqlLike());
    query = null;
} catch (e) {
    console.log("dumplicated calls should be ok :" + e);
}

limit⁸⁺

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

Creates a Query object to specify the number of results and where to start.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Return value

Example

try {
    let query = new distributedData.Query();
    query.notEqualTo("field", "value");
    query.limit("total", "offset");
    console.log("query is " + query.getSqlLike());
    query = null;
} catch (e) {
    console.log("dumplicated calls should be ok :" + e);
}

isNotNull⁸⁺

isNotNull(field: string): Query

Creates a Query object with a specified field that is not null.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Return value

Example

try {
    let query = new distributedData.Query();
    query.isNotNull("field");
    console.log("query is " + query.getSqlLike());
    query = null;
} catch (e) {
    console.log("dumplicated calls should be ok :" + e);
}

beginGroup⁸⁺

beginGroup(): Query

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Example

try {
    let query = new distributedData.Query();
    query.beginGroup();
    query.isNotNull("field");
    query.endGroup();
    console.log("query is " + query.getSqlLike());
    query = null;
} catch (e) {
    console.log("dumplicated calls should be ok :" + e);
}

endGroup⁸⁺

endGroup(): Query

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Example

try {
    let query = new distributedData.Query();
    query.beginGroup();
    query.isNotNull("field");
    query.endGroup();
    console.log("query is " + query.getSqlLike());
    query = null;
} catch (e) {
    console.log("dumplicated calls should be ok :" + e);
}

prefixKey⁸⁺

prefixKey(prefix: string): Query

Creates a Query object with a specified key prefix.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Return value

Example

try {
    let query = new distributedData.Query();
    query.prefixKey("$.name");
    query.prefixKey("0");
    console.log("query is " + query.getSqlLike());
    query = null;
} catch (e) {
    console.log("dumplicated calls should be ok :" + e);
}

setSuggestIndex⁸⁺

setSuggestIndex(index: string): Query

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Return value

Example

try {
    let query = new distributedData.Query();
    query.setSuggestIndex("$.name");
    query.setSuggestIndex("0");
    console.log("query is " + query.getSqlLike());
    query = null;
} catch (e) {
   console.log("dumplicated calls should be ok :" + e);
}

deviceId⁸⁺

deviceId(deviceId:string):Query

Creates a Query object with the device ID as the key prefix.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Return value

Example

try {
    let query = new distributedData.Query();
    query.deviceId("deviceId");
    console.log("query is " + query.getSqlLike());
} catch (e) {
    console.log("should be ok on Method Chaining : " + e);
}

getSqlLike⁸⁺

getSqlLike():string

Obtains the query statement of this Query object.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Example

try {
    let query = new distributedData.Query();
    let sql1 = query.getSqlLike();
    console.log("GetSqlLike sql=" + sql1);
} catch (e) {
    console.log("dumplicated calls should be ok : " + e);
}

KVStore

Provides methods to manage data in a KV store, for example, adding or deleting data and subscribing to data changes or completion of data synchronization. Before calling any method in KVStore, you must use getKVStore to obtain a KVStore object.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

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

Example

let kvStore;
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, function (err,data) {
        if (err != undefined) {
            console.log("put err: " + JSON.stringify(err));
            return;
        }
        console.log("put success");
    });
}catch (e) {
    console.log("An unexpected error occurred. Error:" + e);
}

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

Return value

Example

let kvStore;
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((data) => {
        console.log("put success: " + JSON.stringify(data));
    }).catch((err) => {
        console.log("put err: " + JSON.stringify(err));
    });
}catch (e) {
    console.log("An unexpected error occurred. Error:" + e);
}

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

Example

let kvStore;
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, function (err,data) {
        if (err != undefined) {
            console.log("put err: " + JSON.stringify(err));
            return;
        }
        console.log("put success");
        kvStore.delete(KEY_TEST_STRING_ELEMENT, function (err,data) {
            if (err != undefined) {
                console.log("delete err: " + JSON.stringify(err));
                return;
            }
            console.log("delete success");
        });
    });
}catch (e) {
    console.log("An unexpected error occurred. Error:" + e);
}

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

Return value

Example

let kvStore;
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((data) => {
        console.log("put success: " + JSON.stringify(data));
        kvStore.delete(KEY_TEST_STRING_ELEMENT).then((data) => {
            console.log("delete success");
        }).catch((err) => {
            console.log("delete err: " + JSON.stringify(err));
        });
    }).catch((err) => {
        console.log("put err: " + JSON.stringify(err));
    });
}catch (e) {
    console.log("An unexpected error occurred. Error:" + e);
}

on('dataChange')

on(event: 'dataChange', type: SubscribeType, observer: Callback<ChangeNotification>): void

Subscribes to data changes of the specified type. This API uses a synchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Example

let kvStore;
kvStore.on('dataChange', distributedData.SubscribeType.SUBSCRIBE_TYPE_LOCAL, function (data) {
    console.log("dataChange callback call data: " + JSON.stringify(data));
});

on('syncComplete')

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

Subscribes to data synchronization completion events. This API uses a synchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Example

let kvStore;
kvStore.on('syncComplete', function (data) {
    console.log("callback call data: " + data);
});

off('dataChange')⁸⁺

off(event:'dataChange', observer?: Callback<ChangeNotification>): void

Unsubscribes from data change events. This API uses a synchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Example

let kvStore;
kvStore.on('dataChange', function (data) {
    console.log("callback call data: " + data);
});
kvStore.off('dataChange', function (data) {
    console.log("callback call data: " + data);
});

putBatch⁸⁺

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

Inserts KV pairs in batches to this KV store. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Example

let kvStore;
try {
    let entries = [];
    for (var i = 0; i < 10; i++) {
        var key = 'batch_test_string_key';
        var entry = {
            key : key + i,
            value : {
                type : distributedData.ValueType.STRING,
                value : 'batch_test_string_value'
            }
        }
        entries.push(entry);
    }
    console.log('entries: ' + JSON.stringify(entries));
    kvStore.putBatch(entries, async function (err,data) {
        console.log('putBatch success');
        await kvStore.getEntries('batch_test_string_key', function (err,entrys) {
            console.log('getEntries success');
            console.log('entrys.length: ' + entrys.length);
            console.log('entrys[0]: ' + JSON.stringify(entrys[0]));
        });
    });
}catch(e) {
    console.log('PutBatch e ' + e);
}

putBatch⁸⁺

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

Inserts KV pairs in batches to this KV store. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Return value

Example

let kvStore;
try {
    let entries = [];
    for (var i = 0; i < 10; i++) {
        var key = 'batch_test_string_key';
        var entry = {
            key : key + i,
            value : {
                type : distributedData.ValueType.STRING,
                value : 'batch_test_string_value'
            }
        }
        entries.push(entry);
    }
    console.log('entries: ' + JSON.stringify(entries));
    kvStore.putBatch(entries).then(async (err) => {
        console.log('putBatch success');
        await kvStore.getEntries('batch_test_string_key').then((entrys) => {
            console.log('getEntries success');
            console.log('PutBatch ' + JSON.stringify(entries));
        }).catch((err) => {
            console.log('getEntries fail ' + JSON.stringify(err));
        });
    }).catch((err) => {
        console.log('putBatch fail ' + JSON.stringify(err));
    });
}catch(e) {
    console.log('PutBatch e ' + e);
}

deleteBatch⁸⁺

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

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Example

let kvStore;
try {
    let entries = [];
    let keys = [];
    for (var i = 0; i < 5; i++) {
        var key = 'batch_test_string_key';
        var entry = {
            key : key + i,
            value : {
                type : distributedData.ValueType.STRING,
                value : 'batch_test_string_value'
            }
        }
        entries.push(entry);
        keys.push(key + i);
    }
    console.log('entries: ' + JSON.stringify(entries));
    kvStore.putBatch(entries, async function (err,data) {
        console.log('putBatch success');
        await kvStore.deleteBatch(keys, async function (err,data) {
            console.log('deleteBatch success');
        });
    });
}catch(e) {
    console.log('DeleteBatch e ' + e);
}

deleteBatch⁸⁺

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

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Return value

Example

let kvStore;
try {
    let entries = [];
    let keys = [];
    for (var i = 0; i < 5; i++) {
        var key = 'batch_test_string_key';
        var entry = {
            key : key + i,
            value : {
                type : distributedData.ValueType.STRING,
                value : 'batch_test_string_value'
            }
        }
        entries.push(entry);
        keys.push(key + i);
    }
    console.log('entries: ' + JSON.stringify(entries));
    kvStore.putBatch(entries).then(async (err) => {
        console.log('putBatch success');
        await kvStore.deleteBatch(keys).then((err) => {
            console.log('deleteBatch success');
        }).catch((err) => {
            console.log('deleteBatch fail ' + JSON.stringify(err));
        });
    }).catch((err) => {
        console.log('putBatch fail ' + JSON.stringify(err));
    });
}catch(e) {
    console.log('DeleteBatch e ' + e);
}

startTransaction⁸⁺

startTransaction(callback: AsyncCallback<void>): void

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Example

let kvStore;
function putBatchString(len, prefix) {
    let entries = [];
    for (var i = 0; i < len; i++) {
        var entry = {
            key : prefix + i,
            value : {
                type : distributedData.ValueType.STRING,
                value : 'batch_test_string_value'
            }
        }
        entries.push(entry);
    }
    return entries;
}
try {
    var count = 0;
    kvStore.on('dataChange', 0, function (data) {
        console.log('startTransaction 0' + data)
        count++;
    });
    kvStore.startTransaction(async function (err,data) {
        console.log('startTransaction success');
        let entries = putBatchString(10, 'batch_test_string_key');
        console.log('entries: ' + JSON.stringify(entries));
        await kvStore.putBatch(entries, async function (err,data) {
            console.log('putBatch success');
        });
    });
}catch(e) {
    console.log('startTransaction e ' + e);
}

startTransaction⁸⁺

startTransaction(): Promise<void>

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Example

let kvStore;
try {
    var count = 0;
    kvStore.on('dataChange', distributedData.SubscribeType.SUBSCRIBE_TYPE_ALL, function (data) {
        console.log('startTransaction ' + JSON.stringify(data));
        count++;
    });
    kvStore.startTransaction().then(async (err) => {
        console.log('startTransaction success');
    }).catch((err) => {
        console.log('startTransaction fail ' + JSON.stringify(err));
    });
}catch(e) {
    console.log('startTransaction e ' + e);
}

commit⁸⁺

commit(callback: AsyncCallback<void>): void

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Example

let kvStore;
try {
    kvStore.commit(function (err,data) {
        if (err == undefined) {
            console.log('commit success');
        } else {
            console.log('commit fail');
        }
    });
}catch(e) {
    console.log('Commit e ' + e);
}

commit⁸⁺

commit(): Promise<void>

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Example

let kvStore;
try {
    kvStore.commit().then(async (err) => {
        console.log('commit success');
    }).catch((err) => {
        console.log('commit fail ' + JSON.stringify(err));
    });
}catch(e) {
    console.log('Commit e ' + e);
}

rollback⁸⁺

rollback(callback: AsyncCallback<void>): void

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Example

let kvStore;
try {
    kvStore.rollback(function (err,data) {
        if (err == undefined) {
            console.log('commit success');
        } else {
            console.log('commit fail');
        }
    });
}catch(e) {
    console.log('Rollback e ' + e);
}

rollback⁸⁺

rollback(): Promise<void>

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Return value

Example

let kvStore;
try {
    kvStore.rollback().then(async (err) => {
        console.log('rollback success');
    }).catch((err) => {
        console.log('rollback fail ' + JSON.stringify(err));
    });
}catch(e) {
    console.log('Rollback e ' + e);
}

enableSync⁸⁺

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

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Example

let kvStore;
try {
    kvStore.enableSync(true, function (err,data) {
        if (err == undefined) {
            console.log('enableSync success');
        } else {
            console.log('enableSync fail');
        }
    });
}catch(e) {
    console.log('EnableSync e ' + e);
}

enableSync⁸⁺

enableSync(enabled: boolean): Promise<void>

Enables or disables data synchronization. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Return value

Example

let kvStore;
try {
    kvStore.enableSync(true).then((err) => {
        console.log('enableSync success');
    }).catch((err) => {
        console.log('enableSync fail ' + JSON.stringify(err));
    });
}catch(e) {
    console.log('EnableSync e ' + e);
}

setSyncRange⁸⁺

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

Example

let kvStore;
try {
    const localLabels = ['A', 'B'];
    const remoteSupportLabels = ['C', 'D'];
    kvStore.setSyncRange(localLabels, remoteSupportLabels, function (err,data) {
        console.log('SetSyncRange put success');
    });
}catch(e) {
    console.log('SetSyncRange e ' + e);
}

setSyncRange⁸⁺

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

Return value

Example

let kvStore;
try {
    const localLabels = ['A', 'B'];
    const remoteSupportLabels = ['C', 'D'];
    kvStore.setSyncRange(localLabels, remoteSupportLabels).then((err) => {
        console.log('setSyncRange success');
    }).catch((err) => {
        console.log('delete fail ' + err);
    });
}catch(e) {
    console.log('SetSyncRange e ' + e);
}

SubscribeType

Defines the subscription type.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

ChangeNotification

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Entry

Defines the KV pairs stored in the KV store.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Value

Defines the value in a KV pair.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

ValueType

Enumerates the types of values in KV pairs.

These value types can be used only by internal applications.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

SingleKVStore

Provides methods to query and synchronize data in a single KV store. This class inherits from KVStore. Before calling any method in SingleKVStore, you must use getKVStore to obtain a SingleKVStore object.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

get

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

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Example

let kvStore;
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, function (err,data) {
        if (err != undefined) {
            console.log("put err: " + JSON.stringify(err));
            return;
        }
        console.log("put success");
        kvStore.get(KEY_TEST_STRING_ELEMENT, function (err,data) {
            console.log("get success data: " + data);
        });
    });
}catch (e) {
    console.log("An unexpected error occurred. Error:" + e);
}

get

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

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Return value

Example

let kvStore;
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((data) => {
        console.log("put success: " + JSON.stringify(data));
        kvStore.get(KEY_TEST_STRING_ELEMENT).then((data) => {
            console.log("get success data: " + data);
        }).catch((err) => {
            console.log("get err: " + JSON.stringify(err));
        });
    }).catch((err) => {
        console.log("put err: " + JSON.stringify(err));
    });
}catch (e) {
    console.log("An unexpected error occurred. Error:" + e);
}

getEntries⁸⁺

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

Obtains the 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

Example

let kvStore;
try {
    let entries = [];
    for (var i = 0; i < 10; i++) {
        var key = 'batch_test_number_key';
        var entry = {
            key : key + i,
            value : {
                type : distributedData.ValueType.INTEGER,
                value : 222
            }
        }
        entries.push(entry);
    }
    kvStore.putBatch(entries, async function (err,data) {
        console.log('putBatch success');
        await kvStore.getEntries('batch_test_number_key', function (err,entrys) {
            console.log('getEntries success');
            console.log('entrys.length: ' + entrys.length);
            console.log('entrys[0]: ' + JSON.stringify(entrys[0]));
        });
    });
}catch(e) {
    console.log('PutBatch e ' + e);
}

getEntries⁸⁺

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

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Return value

Example

let kvStore;
try {
    let entries = [];
    for (var i = 0; i < 10; i++) {
        var key = 'batch_test_string_key';
        var entry = {
            key : key + i,
            value : {
                type : distributedData.ValueType.STRING,
                value : 'batch_test_string_value'
            }
        }
        entries.push(entry);
    }
    console.log('entries: ' + entries);
    kvStore.putBatch(entries).then(async (err) => {
        console.log('putBatch success');
        await kvStore.getEntries('batch_test_string_key').then((entrys) => {
            console.log('getEntries success');
            console.log('entrys.length: ' + entrys.length);
            console.log('entrys[0]: ' + JSON.stringify(entrys[0]));
            console.log('entrys[0].value: ' + JSON.stringify(entrys[0].value));
            console.log('entrys[0].value.value: ' + entrys[0].value.value);
        }).catch((err) => {
            console.log('getEntries fail ' + JSON.stringify(err));
        });
    }).catch((err) => {
        console.log('putBatch fail ' + JSON.stringify(err));
    });
}catch(e) {
    console.log('PutBatch e ' + e);
}

getEntries⁸⁺

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

Example

let kvStore;
try {
    var arr = new Uint8Array([21,31]);
    let entries = [];
    for (var i = 0; i < 10; i++) {
        var key = 'batch_test_bool_key';
        var entry = {
            key : key + i,
            value : {
                type : distributedData.ValueType.BYTE_ARRAY,
                value : arr
            }
        }
        entries.push(entry);
    }
    console.log('entries: ' + JSON.stringify(entries));
    kvStore.putBatch(entries, async function (err,data) {
        console.log('putBatch success');
        const query = new distributedData.Query();
        query.prefixKey("batch_test");
        await kvStore.getEntries(query, function (err,entrys) {
            console.log('getEntries success');
            console.log('entrys.length: ' + entrys.length);
            console.log('entrys[0]: ' + JSON.stringify(entrys[0]));
        });
    });
    console.log('GetEntries success');
}catch(e) {
    console.log('GetEntries e ' + e);
}

getEntries⁸⁺

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

Return value

Example

try {
    var arr = new Uint8Array([21,31]);
    let entries = [];
    for (var i = 0; i < 10; i++) {
        var key = 'batch_test_bool_key';
        var entry = {
            key : key + i,
            value : {
                type : distributedData.ValueType.BYTE_ARRAY,
                value : arr
            }
        }
        entries.push(entry);
    }
    console.log('entries: ' + JSON.stringify(entries));
    kvStore.putBatch(entries).then(async (err) => {
        console.log('putBatch success');
        const query = new distributedData.Query();
        query.prefixKey("batch_test");
        await kvStore.getEntries(query).then((entrys) => {
            console.log('getEntries success');
        }).catch((err) => {
            console.log('getEntries fail ' + JSON.stringify(err));
        });
    }).catch((err) => {
        console.log('GetEntries putBatch fail ' + JSON.stringify(err))
    });
    console.log('GetEntries success');
}catch(e) {
    console.log('GetEntries e ' + e);
}

getResultSet⁸⁺

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

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Example

let kvStore;
try {
    let resultSet;
    let entries = [];
    for (var i = 0; i < 10; i++) {
        var key = 'batch_test_string_key';
        var entry = {
            key : key + i,
            value : {
                type : distributedData.ValueType.STRING,
                value : 'batch_test_string_value'
            }
        }
        entries.push(entry);
    }
    kvStore.putBatch(entries, async function (err, data) {
        console.log('GetResultSet putBatch success');
        await kvStore.getResultSet('batch_test_string_key', async function (err, result) {
            console.log('GetResultSet getResultSet success');
            resultSet = result;
            kvStore.closeResultSet(resultSet, function (err, data) {
                console.log('GetResultSet closeResultSet success');
            })
        });
    });
}catch(e) {
    console.log('GetResultSet e ' + e);
}

getResultSet⁸⁺

getResultSet(keyPrefix: string): Promise<KvStoreResultSet>

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Return value

Example

let kvStore;
try {
    let resultSet;
    let entries = [];
    for (var i = 0; i < 10; i++) {
        var key = 'batch_test_string_key';
        var entry = {
            key : key + i,
            value : {
                type : distributedData.ValueType.STRING,
                value : 'batch_test_string_value'
            }
        }
        entries.push(entry);
    }
    kvStore.putBatch(entries).then(async (err) => {
        console.log('putBatch success');
    }).catch((err) => {
        console.log('PutBatch putBatch fail ' + JSON.stringify(err));
    });
    kvStore.getResultSet('batch_test_string_key').then((result) => {
        console.log('GetResult getResultSet success');
        resultSet = result;
    }).catch((err) => {
        console.log('getResultSet fail ' + JSON.stringify(err));
    });
    kvStore.closeResultSet(resultSet).then((err) => {
        console.log('GetResult closeResultSet success');
    }).catch((err) => {
        console.log('closeResultSet fail ' + JSON.stringify(err));
    });
}catch(e) {
    console.log('GetResult e ' + e);
}

getResultSet⁸⁺

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

Obtains the 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

Example

let kvStore;
try {
    let resultSet;
    let entries = [];
    for (var i = 0; i < 10; i++) {
        var key = 'batch_test_string_key';
        var entry = {
            key : key + i,
            value : {
                type : distributedData.ValueType.STRING,
                value : 'batch_test_string_value'
            }
        }
        entries.push(entry);
    }
    kvStore.putBatch(entries, async function (err, data) {
        console.log('putBatch success');
        const query = new distributedData.Query();
        query.prefixKey("batch_test");
        await kvStore.getResultSet(query, async function (err, result) {
            console.log('getResultSet success');
            resultSet = result;
        });
    });
} catch(e) {
    console.log('GetResultSet e ' + e);
}

getResultSet⁸⁺

getResultSet(query: Query): Promise<KvStoreResultSet>

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

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Return value

Example

let kvStore;
try {
    let resultSet;
    let entries = [];
    for (var i = 0; i < 10; i++) {
        var key = 'batch_test_string_key';
        var entry = {
            key : key + i,
            value : {
                type : distributedData.ValueType.STRING,
                value : 'batch_test_string_value'
            }
        }
        entries.push(entry);
    }
    kvStore.putBatch(entries).then(async (err) => {
        console.log('putBatch success');
    }).catch((err) => {
        console.log('putBatch fail ' + JSON.stringify(err));
    });
    const query = new distributedData.Query();
    query.prefixKey("batch_test");
    kvStore.getResultSet(query).then((result) => {
        console.log(' getResultSet success');
        resultSet = result;
    }).catch((err) => {
        console.log('getResultSet fail ' + JSON.stringify(err));
    });
}catch(e) {
    console.log('GetResultSet e ' + e);
}

closeResultSet⁸⁺

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

Closes the KvStoreResultSet object obtained by getResultSet. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Example

let kvStore;
try {
    let resultSet = null;
    kvStore.closeResultSet(resultSet, function (err, data) {
        if (err == undefined) {
            console.log('closeResultSet success');
        } else {
            console.log('closeResultSet fail');
        }
    });
}catch(e) {
    console.log('CloseResultSet e ' + e);
}

closeResultSet⁸⁺

closeResultSet(resultSet: KvStoreResultSet): Promise<void>

Closes the KvStoreResultSet object obtained by getResultSet. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Return value

Example

let kvStore;
try {
    let resultSet = null;
    kvStore.closeResultSet(resultSet).then(() => {
        console.log('closeResultSet success');
    }).catch((err) => {
        console.log('closeResultSet fail ' + JSON.stringify(err));
    });
}catch(e) {
    console.log('CloseResultSet e ' + e);
}

getResultSize⁸⁺

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

Example

let kvStore;
try {
    let entries = [];
    for (var i = 0; i < 10; i++) {
        var key = 'batch_test_string_key';
        var entry = {
            key : key + i,
            value : {
                type : distributedData.ValueType.STRING,
                value : 'batch_test_string_value'
            }
        }
        entries.push(entry);
    }
    kvStore.putBatch(entries, async function (err, data) {
        console.log('putBatch success');
        const query = new distributedData.Query();
        query.prefixKey("batch_test");
        await kvStore.getResultSize(query, async function (err, resultSize) {
            console.log('getResultSet success');
        });
    });
} catch(e) {
    console.log('GetResultSize e ' + e);
}

getResultSize⁸⁺

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

Return value

Example

let kvStore;
try {
    let entries = [];
    for (var i = 0; i < 10; i++) {
        var key = 'batch_test_string_key';
        var entry = {
            key : key + i,
            value : {
                type : distributedData.ValueType.STRING,
                value : 'batch_test_string_value'
            }
        }
        entries.push(entry);
    }
    kvStore.putBatch(entries).then(async (err) => {
        console.log('putBatch success');
    }).catch((err) => {
        console.log('putBatch fail ' + JSON.stringify(err));
    });
    const query = new distributedData.Query();
    query.prefixKey("batch_test");
    kvStore.getResultSize(query).then((resultSize) => {
        console.log('getResultSet success');
    }).catch((err) => {
        console.log('getResultSet fail ' + JSON.stringify(err));
    });
}catch(e) {
    console.log('GetResultSize e ' + e);
}

removeDeviceData⁸⁺

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

Deletes data of a device. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Example

let kvStore;
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 function (err,data) {
        console.log('put success');
        const deviceid = 'no_exist_device_id';
        await kvStore.removeDeviceData(deviceid, async function (err,data) {
            if (err == undefined) {
                console.log('removeDeviceData success');
            } else {
                console.log('removeDeviceData fail');
                await kvStore.get(KEY_TEST_STRING_ELEMENT, async function (err,data) {
                    console.log('RemoveDeviceData get success');
                });
            }
        });
    });
}catch(e) {
    console.log('RemoveDeviceData e ' + e);
}

removeDeviceData⁸⁺

removeDeviceData(deviceId: string): Promise<void>

Deletes data of a device. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Return value

Example

let kvStore;
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((err) => {
        console.log('removeDeviceData put success');
    }).catch((err) => {
        console.log('put fail ' + JSON.stringify(err));
    });
    const deviceid = 'no_exist_device_id';
    kvStore.removeDeviceData(deviceid).then((err) => {
        console.log('removeDeviceData success');
    }).catch((err) => {
        console.log('removeDeviceData fail ' + JSON.stringify(err));
    });
    kvStore.get(KEY_TEST_STRING_ELEMENT).then((data) => {
        console.log('get success data:' + data);
    }).catch((err) => {
        console.log('RemoveDeviceData get fail ' + JSON.stringify(err));
    });
}catch(e) {
    console.log('RemoveDeviceData e ' + e);
}

on('syncComplete')⁸⁺

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

Subscribes to the synchronization completion events. This API uses a synchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Example

let kvStore;
const KEY_TEST_FLOAT_ELEMENT = 'key_test_float';
const VALUE_TEST_FLOAT_ELEMENT = 321.12;
try {
    kvStore.on('syncComplete', function (data) {
        console.log('syncComplete ' + data)
    });
    kvStore.put(KEY_TEST_FLOAT_ELEMENT, VALUE_TEST_FLOAT_ELEMENT).then((data) => {
        console.log('syncComplete put success');
    }).catch((error) => {
        console.log('syncComplete put fail ' + error);
    });
}catch(e) {
    console.log('syncComplete put e ' + e);
}

off('syncComplete')⁸⁺

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

Unsubscribes from the synchronization completion events. This API uses a synchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Example

let kvStore;
try {
    const func = function (data) {
        console.log('syncComplete ' + data)
    };
    kvStore.on('syncComplete', func);
    kvStore.off('syncComplete', func);
}catch(e) {
    console.log('syncComplete e ' + e);
}

sync

sync(deviceIdList: string[], mode: SyncMode, allowedDelayMs?: number): void

Manually triggers KV store synchronization synchronously.

Required permissions: ohos.permission.DISTRIBUTED_DATASYNC

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Example

let kvStore;
kvStore.sync('deviceIds', distributedData.SyncMode.PULL_ONLY, 1000);

setSyncParam⁸⁺

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

Sets the default delay of database synchronization. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Example

let kvStore;
try {
    const defaultAllowedDelayMs = 500;
    kvStore.setSyncParam(defaultAllowedDelayMs, function (err,data) {
        console.log('SetSyncParam put success');
    });
}catch(e) {
    console.log('testSingleKvStoreSetSyncParam e ' + e);
}

setSyncParam⁸⁺

setSyncParam(defaultAllowedDelayMs: number): Promise<void>

Sets the default delay of database synchronization. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.Core

Parameters

Return value

Example

let kvStore;
try {
    const defaultAllowedDelayMs = 500;
    kvStore.setSyncParam(defaultAllowedDelayMs).then((err) => {
        console.log('SetSyncParam put success');
    }).catch((err) => {
        console.log('SetSyncParam put fail ' + JSON.stringify(err));
    });
}catch(e) {
    console.log('SetSyncParam e ' + e);
}

getSecurityLevel⁸⁺

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

Example

let kvStore;
try {
    kvStore.getSecurityLevel(function (err,data) {
        console.log('getSecurityLevel success');
    });
}catch(e) {
    console.log('GetSecurityLeve e ' + e);
}

getSecurityLevel⁸⁺

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

Example

let kvStore;
try {
    kvStore.getSecurityLevel().then((data) => {
        console.log(' getSecurityLevel success');
    }).catch((err) => {
        console.log('getSecurityLevel fail ' + JSON.stringify(err));
    });
}catch(e) {
    console.log('GetSecurityLeve e ' + e);
}

DeviceKVStore⁸⁺

Provides methods to manage distributed data by device in the distributed system. This class inherits from KVStore and provides data query and synchronization methods. Before calling any method in DeviceKVStore, you must use getKVStore to obtain a DeviceKVStore object.

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

get⁸⁺

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

Obtains the string value that matches the specified key for a device. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Example

let kvStore;
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 function (err,data) {
        console.log('put success');
        kvStore.get('localDeviceId', KEY_TEST_STRING_ELEMENT, function (err,data) {
            console.log('get success');
        });
    })
}catch(e) {
    console.log('get e' + e);
}

get⁸⁺

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

Obtains the string value that matches the specified key for a device. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Return value

Example

let kvStore;
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 (data) => {
        console.log(' put success');
        kvStore.get('localDeviceId', KEY_TEST_STRING_ELEMENT).then((data) => {
            console.log('get success');
        }).catch((err) => {
            console.log('get fail ' + JSON.stringify(err));
        });
    }).catch((error) => {
        console.log('put error' + error);
    });
} catch (e) {
    console.log('Get e ' + e);
}

getEntries⁸⁺

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

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

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Example

let kvStore;
try {
    let entries = [];
    for (var i = 0; i < 10; i++) {
        var key = 'batch_test_string_key';
        var entry = {
            key : key + i,
            value : {
                type : distributedData.ValueType.STRING,
                value : 'batch_test_string_value'
            }
        }
        entries.push(entry);
    }
    console.log('entries: ' + entries);
    kvStore.putBatch(entries, async function (err,data) {
        console.log('putBatch success');
        await kvStore.getEntries('localDeviceId', 'batch_test_string_key', function (err,entrys) {
            console.log('getEntries success');
            console.log('entrys.length: ' + entrys.length);
            console.log('entrys[0]: ' + JSON.stringify(entrys[0]));
        });
    });
}catch(e) {
    console.log('PutBatch e ' + e);
}

getEntries⁸⁺

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

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

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Return value

Example

let kvStore;
try {
    let entries = [];
    for (var i = 0; i < 10; i++) {
        var key = 'batch_test_string_key';
        var entry = {
            key : key + i,
            value : {
                type : distributedData.ValueType.STRING,
                value : 'batch_test_string_value'
            }
        }
        entries.push(entry);
    }
    console.log('entries: ' + entries);
    kvStore.putBatch(entries).then(async (err) => {
        console.log('putBatch success');
        await kvStore.getEntries('localDeviceId', 'batch_test_string_key').then((entrys) => {
            console.log('getEntries success');
            console.log('entrys.length: ' + entrys.length);
            console.log('entrys[0]: ' + JSON.stringify(entrys[0]));
            console.log('entrys[0].value: ' + JSON.stringify(entrys[0].value));
            console.log('entrys[0].value.value: ' + entrys[0].value.value);
        }).catch((err) => {
            console.log('getEntries fail ' + JSON.stringify(err));
        });
    }).catch((err) => {
        console.log('putBatch fail ' + JSON.stringify(err));
    });
}catch(e) {
    console.log('PutBatch e ' + e);
}

getEntries⁸⁺

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.DistributedKVStore

Parameters

Example

let kvStore;
try {
    var arr = new Uint8Array([21,31]);
    let entries = [];
    for (var i = 0; i < 10; i++) {
        var key = 'batch_test_bool_key';
        var entry = {
            key : key + i,
            value : {
                type : distributedData.ValueType.BYTE_ARRAY,
                value : arr
            }
        }
        entries.push(entry);
    }
    console.log('entries: ' + JSON.stringify(entries));
    kvStore.putBatch(entries, async function (err,data) {
        console.log('putBatch success');
        expect(err == undefined).assertTrue();
        const query = new distributedData.Query();
        query.prefixKey("batch_test");
        query.deviceId('localDeviceId');
        await kvStore.getEntries(query, function (err,entrys) {
            console.log('getEntries success');
            console.log('entrys.length: ' + entrys.length);
            console.log('entrys[0]: ' + JSON.stringify(entrys[0]));
        });
    });
    console.log('GetEntries success');
}catch(e) {
    console.log('GetEntries e ' + e);
}

getEntries⁸⁺

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.DistributedKVStore

Parameters

Return value

Example

let kvStore;
try {
    var arr = new Uint8Array([21,31]);
    let entries = [];
    for (var i = 0; i < 10; i++) {
        var key = 'batch_test_bool_key';
        var entry = {
            key : key + i,
            value : {
                type : distributedData.ValueType.BYTE_ARRAY,
                value : arr
            }
        }
        entries.push(entry);
    }
    console.log('entries: ' + JSON.stringify(entries));
    kvStore.putBatch(entries).then(async (err) => {
        console.log('putBatch success');
        const query = new distributedData.Query();
        query.prefixKey("batch_test");
        await kvStore.getEntries(query).then((entrys) => {
            console.log('getEntries success');
        }).catch((err) => {
            console.log('getEntries fail ' + JSON.stringify(err));
        });
    }).catch((err) => {
        console.log('GetEntries putBatch fail ' + JSON.stringify(err))
    });
    console.log('GetEntries success');
}catch(e) {
    console.log('GetEntries e ' + e);
}

getEntries⁸⁺

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

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

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Example

let kvStore;
try {
    var arr = new Uint8Array([21,31]);
    let entries = [];
    for (var i = 0; i < 10; i++) {
        var key = 'batch_test_bool_key';
        var entry = {
            key : key + i,
            value : {
                type : distributedData.ValueType.BYTE_ARRAY,
                value : arr
            }
        }
        entries.push(entry);
    }
    console.log('entries: ' + JSON.stringify(entries));
    kvStore.putBatch(entries, async function (err,data) {
        console.log('putBatch success');
        expect(err == undefined).assertTrue();
        var query = new distributedData.Query();
        query.deviceId('localDeviceId');
        query.prefixKey("batch_test");
        await kvStore.getEntries('localDeviceId', query, function (err,entrys) {
            console.log('getEntries success');
            console.log('entrys.length: ' + entrys.length);
            console.log('entrys[0]: ' + JSON.stringify(entrys[0]));
        })
    });
    console.log('GetEntries success');
}catch(e) {
    console.log('GetEntries e ' + e);
}

getEntries⁸⁺

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

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

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Return value

Example

let kvStore;
try {
    var arr = new Uint8Array([21,31]);
    let entries = [];
    for (var i = 0; i < 10; i++) {
        var key = 'batch_test_bool_key';
        var entry = {
            key : key + i,
            value : {
                type : distributedData.ValueType.BYTE_ARRAY,
                value : arr
            }
        }
        entries.push(entry);
    }
    console.log('entries: ' + JSON.stringify(entries));
    kvStore.putBatch(entries).then(async (err) => {
        console.log('putBatch success');
        var query = new distributedData.Query();
        query.deviceId('localDeviceId');
        query.prefixKey("batch_test");
        await kvStore.getEntries('localDeviceId', query).then((entrys) => {
            console.log('getEntries success');
        }).catch((err) => {
            console.log('getEntries fail ' + JSON.stringify(err));
        });
    }).catch((err) => {
        console.log('putBatch fail ' + JSON.stringify(err));
    });
    console.log('GetEntries success');
}catch(e) {
    console.log('GetEntries e ' + e);
}

getResultSet⁸⁺

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

Obtains the KvStoreResultSet object that matches the specified key prefix for a device. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Example

let kvStore;
try {
    let resultSet;
    kvStore.getResultSet('localDeviceId', 'batch_test_string_key', async function (err, result) {
        console.log('getResultSet success');
        resultSet = result;
        await kvStore.closeResultSet(resultSet, function (err, data) {
            console.log('closeResultSet success');
        })
    });
}catch(e) {
    console.log('GetResultSet e ' + e);
}

getResultSet⁸⁺

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

Obtains the KvStoreResultSet object that matches the specified key prefix for a device. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Return value

Example

let kvStore;
try {
    let resultSet;
    kvStore.getResultSet('localDeviceId', 'batch_test_string_key').then((result) => {
        console.log('getResultSet success');
        resultSet = result;
    }).catch((err) => {
        console.log('getResultSet fail ' + JSON.stringify(err));
    });
    kvStore.closeResultSet(resultSet).then((err) => {
        console.log('closeResultSet success');
    }).catch((err) => {
        console.log('closeResultSet fail ' + JSON.stringify(err));
    });
}catch(e) {
    console.log('GetResultSet e ' + e);
}

getResultSet⁸⁺

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

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

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Example

let kvStore;
try {
    let resultSet;
    let entries = [];
    for (var i = 0; i < 10; i++) {
        var key = 'batch_test_string_key';
        var entry = {
            key : key + i,
            value : {
                type : distributedData.ValueType.STRING,
                value : 'batch_test_string_value'
            }
        }
        entries.push(entry);
    }
    kvStore.putBatch(entries, async function (err, data) {
        console.log('putBatch success');
        const query = new distributedData.Query();
        query.prefixKey("batch_test");
        query.deviceId('localDeviceId');
        await kvStore.getResultSet(query, async function (err, result) {
            console.log('getResultSet success');
            resultSet = result;
            await kvStore.closeResultSet(resultSet, function (err, data) {
                console.log('closeResultSet success');
            })
        });
    });
} catch(e) {
    console.log('GetResultSet e ' + e);
}

getResultSet⁸⁺

getResultSet(query: Query): Promise<KvStoreResultSet>

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

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Return value

Example

let kvStore;
try {
    let resultSet;
    let entries = [];
    for (var i = 0; i < 10; i++) {
        var key = 'batch_test_string_key';
        var entry = {
            key : key + i,
            value : {
                type : distributedData.ValueType.STRING,
                value : 'batch_test_string_value'
            }
        }
        entries.push(entry);
    }
    kvStore.putBatch(entries).then(async (err) => {
        console.log('putBatch success');
    }).catch((err) => {
        console.log('putBatch fail ' + err);
    });
    const query = new distributedData.Query();
    query.deviceId('localDeviceId');
    query.prefixKey("batch_test");
    console.log("GetResultSet " + query.getSqlLike());
    kvStore.getResultSet(query).then((result) => {
        console.log('getResultSet success');
        resultSet = result;
    }).catch((err) => {
        console.log('getResultSet fail ' + JSON.stringify(err));
    });
    kvStore.closeResultSet(resultSet).then((err) => {
        console.log('closeResultSet success');
    }).catch((err) => {
        console.log('closeResultSet fail ' + JSON.stringify(err));
    });
}catch(e) {
    console.log('GetResultSet e ' + e);
}

getResultSet⁸⁺

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

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

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Example

let kvStore;
try {
    let resultSet;
    let entries = [];
    for (var i = 0; i < 10; i++) {
        var key = 'batch_test_string_key';
        var entry = {
            key : key + i,
            value : {
                type : distributedData.ValueType.STRING,
                value : 'batch_test_string_value'
            }
        }
        entries.push(entry);
    }
    kvStore.putBatch(entries, async function (err, data) {
        console.log('putBatch success');
        const query = new distributedData.Query();
        query.prefixKey("batch_test");
        await kvStore.getResultSet('localDeviceId', query, async function (err, result) {
            console.log('getResultSet success');
            resultSet = result;
            await kvStore.closeResultSet(resultSet, function (err, data) {
                console.log('closeResultSet success');
            })
        });
    });
} catch(e) {
    console.log('GetResultSet e ' + e);
}

getResultSet⁸⁺

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

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

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Return value

Example

let kvStore;
try {
    let resultSet;
    let entries = [];
    for (var i = 0; i < 10; i++) {
        var key = 'batch_test_string_key';
        var entry = {
            key : key + i,
            value : {
                type : distributedData.ValueType.STRING,
                value : 'batch_test_string_value'
            }
        }
        entries.push(entry);
    }
    kvStore.putBatch(entries).then(async (err) => {
        console.log('GetResultSet putBatch success');
    }).catch((err) => {
        console.log('PutBatch putBatch fail ' + JSON.stringify(err));
    });
    const query = new distributedData.Query();
    query.prefixKey("batch_test");
    kvStore.getResultSet('localDeviceId', query).then((result) => {
        console.log('GetResultSet getResultSet success');
        resultSet = result;
    }).catch((err) => {
        console.log('GetResultSet getResultSet fail ' + JSON.stringify(err));
    });
    query.deviceId('localDeviceId');
    console.log("GetResultSet " + query.getSqlLike());
    kvStore.closeResultSet(resultSet).then((err) => {
        console.log('GetResultSet closeResultSet success');
    }).catch((err) => {
        console.log('GetResultSet closeResultSet fail ' + JSON.stringify(err));
    });

}catch(e) {
    console.log('GetResultSet e ' + e);
}

closeResultSet⁸⁺

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

Closes the KvStoreResultSet object obtained by getResultSet. This API uses an asynchronous callback to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Example

let kvStore;
try {
    console.log('CloseResultSet success');
    let resultSet = null;
    kvStore.closeResultSet(resultSet, function (err, data) {
        if (err == undefined) {
            console.log('closeResultSet success');
        } else {
            console.log('closeResultSet fail');
        }
    });
}catch(e) {
    console.log('CloseResultSet e ' + e);
}

closeResultSet⁸⁺

closeResultSet(resultSet: KvStoreResultSet): Promise<void>

Closes the KvStoreResultSet object obtained by getResultSet. This API uses a promise to return the result.

System capability: SystemCapability.DistributedDataManager.KVStore.DistributedKVStore

Parameters

Return value

Example

let kvStore;
try {
    console.log('CloseResultSet success');
    let resultSet = null;
    kvStore.closeResultSet(resultSet).then(() => {
        console.log('closeResultSet success');
    }).catch((err) => {
        console.log('closeResultSet fail ' + JSON.stringify(err));
    });
}catch(e) {
    console.log('CloseResultSet e ' + e);
}

getResultSize⁸⁺

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.DistributedKVStore

Parameters

Example

let kvStore;
try {
    let entries = [];
    for (var i = 0; i < 10; i++) {
        var key = 'batch_test_string_key';
        var entry = {
            key : key + i,
            value : {
                type : distributedData.ValueType.STRING,
                value : 'batch_test_string_value'
            }
        }
        entries.push(entry);
    }
    kvStore.putBatch(entries, async function (err, data) {
        console.log('putBatch success');
        const query = new distributedData.Query();
        query.prefixKey("batch_test");
        query.deviceId('localDeviceId');
        await kvStore.getResultSize(query, async function (err, resultSize) {
            console.log('getResultSet success');
        });
    });
} catch(e) {
    console.log('GetResultSize e ' + e);
}

getResultSize⁸⁺

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.DistributedKVStore

Parameters