>The initial APIs of this module are supported since API version 7. Newly added APIs will be marked with a superscript to indicate their earliest API version.
> The 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<a name="section68088407422"></a>
<td class="cellrowborder" valign="top" width="61.29%" headers="mcps1.1.5.1.4 "><p id="p1816220320362"><a name="p1816220320362"></a><a name="p1816220320362"></a>Table name in the RDB store.</p>
<td class="cellrowborder" valign="top" width="61.29%" headers="mcps1.1.5.1.4 "><p id="p13948172810562"><a name="p13948172810562"></a><a name="p13948172810562"></a>Column name in the database table.</p>
<td class="cellrowborder" valign="top" width="61.29%" headers="mcps1.1.5.1.4 "><p id="p16532133810511"><a name="p16532133810511"></a><a name="p16532133810511"></a>Column name in the database table.</p>
<td class="cellrowborder" valign="top" width="61.29%" headers="mcps1.1.5.1.4 "><p id="p1595612471811"><a name="p1595612471811"></a><a name="p1595612471811"></a>Column name in the database table.</p>
<td class="cellrowborder" valign="top" width="61.29%" headers="mcps1.1.5.1.4 "><p id="p35911455102217"><a name="p35911455102217"></a><a name="p35911455102217"></a>Column name in the database table.</p>
<td class="cellrowborder" valign="top" width="61.29%" headers="mcps1.1.5.1.4 "><p id="p17593942142517"><a name="p17593942142517"></a><a name="p17593942142517"></a>Column name in the database table.</p>
<td class="cellrowborder" valign="top" width="61.29%" headers="mcps1.1.5.1.4 "><p id="p1996411246271"><a name="p1996411246271"></a><a name="p1996411246271"></a>Column name in the database table.</p>
<td class="cellrowborder" valign="top" width="61.29%" headers="mcps1.1.5.1.4 "><p id="p1529081319307"><a name="p1529081319307"></a><a name="p1529081319307"></a>Column name in the database table.</p>
<td class="cellrowborder" valign="top" width="61.29%" headers="mcps1.1.5.1.4 "><p id="p201222193217"><a name="p201222193217"></a><a name="p201222193217"></a>Column name in the database table.</p>
<td class="cellrowborder" valign="top" width="61.29%" headers="mcps1.1.5.1.4 "><p id="p12823846193519"><a name="p12823846193519"></a><a name="p12823846193519"></a>Column name in the database table.</p>
<td class="cellrowborder" valign="top" width="61.29%" headers="mcps1.1.5.1.4 "><p id="p11585122912376"><a name="p11585122912376"></a><a name="p11585122912376"></a>Column name in the database table.</p>
<td class="cellrowborder" valign="top" width="61.29%" headers="mcps1.1.5.1.4 "><p id="p65868296372"><a name="p65868296372"></a><a name="p65868296372"></a>Minimum value to match the <strong id="b14438191462013"><a name="b14438191462013"></a><a name="b14438191462013"></a>DataAbilityPredicates</strong>.</p>
<td class="cellrowborder" valign="top" width="61.29%" headers="mcps1.1.5.1.4 "><p id="p2022844615374"><a name="p2022844615374"></a><a name="p2022844615374"></a>Maximum value to match the <strong id="b7785102615203"><a name="b7785102615203"></a><a name="b7785102615203"></a>DataAbilityPredicates</strong>.</p>
<td class="cellrowborder" valign="top" width="61.29%" headers="mcps1.1.5.1.4 "><p id="p1981444134313"><a name="p1981444134313"></a><a name="p1981444134313"></a>Column name in the database table.</p>
<td class="cellrowborder" valign="top" width="61.29%" headers="mcps1.1.5.1.4 "><p id="p1381844194316"><a name="p1381844194316"></a><a name="p1381844194316"></a>Minimum value to match the <strong id="b546722092013"><a name="b546722092013"></a><a name="b546722092013"></a>DataAbilityPredicates</strong>.</p>
<td class="cellrowborder" valign="top" width="61.29%" headers="mcps1.1.5.1.4 "><p id="p88354494313"><a name="p88354494313"></a><a name="p88354494313"></a>Maximum value to match the <strong id="b798403114204"><a name="b798403114204"></a><a name="b798403114204"></a>DataAbilityPredicates</strong>.</p>
<td class="cellrowborder" valign="top" width="61.29%" headers="mcps1.1.5.1.4 "><p id="p1691124318464"><a name="p1691124318464"></a><a name="p1691124318464"></a>Column name in the database table.</p>
<td class="cellrowborder" valign="top" width="61.29%" headers="mcps1.1.5.1.4 "><p id="p113631950154917"><a name="p113631950154917"></a><a name="p113631950154917"></a>Column name in the database table.</p>
<td class="cellrowborder" valign="top" width="61.29%" headers="mcps1.1.5.1.4 "><p id="p514164619518"><a name="p514164619518"></a><a name="p514164619518"></a>Column name in the database table.</p>
<td class="cellrowborder" valign="top" width="61.29%" headers="mcps1.1.5.1.4 "><p id="p17334204215534"><a name="p17334204215534"></a><a name="p17334204215534"></a>Column name in the database table.</p>
<td class="cellrowborder" valign="top" width="61.29%" headers="mcps1.1.5.1.4 "><p id="p68841111195510"><a name="p68841111195510"></a><a name="p68841111195510"></a>Column name in the database table.</p>
<td class="cellrowborder" valign="top" width="61.29%" headers="mcps1.1.5.1.4 "><p id="p1387316305811"><a name="p1387316305811"></a><a name="p1387316305811"></a>Column name in the database table.</p>
<td class="cellrowborder" valign="top" width="61.29%" headers="mcps1.1.5.1.4 "><p id="p1517417541634"><a name="p1517417541634"></a><a name="p1517417541634"></a>Maximum number of records in a column.</p>
<td class="cellrowborder" valign="top" width="69.56%" headers="mcps1.1.3.1.2 "><p id="p1556711111755"><a name="p1556711111755"></a><a name="p1556711111755"></a><strong id="b167661054195110"><a name="b167661054195110"></a><a name="b167661054195110"></a>DataAbilityPredicates</strong> that can be used to set the maximum number of records.</p>
</td>
</tr>
</tbody>
</table>
- Example
```
let predicates = new dataAbility.DataAbilityPredicates("EMPLOYEE")
<td class="cellrowborder" valign="top" width="61.29%" headers="mcps1.1.5.1.4 "><p id="p643616810715"><a name="p643616810715"></a><a name="p643616810715"></a>Number of rows to offset from the beginning. The value is a positive integer.</p>
<td class="cellrowborder" valign="top" width="69.56%" headers="mcps1.1.3.1.2 "><p id="p1259123415819"><a name="p1259123415819"></a><a name="p1259123415819"></a><strong id="b73181951193716"><a name="b73181951193716"></a><a name="b73181951193716"></a>DataAbilityPredicates</strong> object that specifies the start position of the returned result.</p>
</td>
</tr>
</tbody>
</table>
- Example
```
let predicates = new dataAbility.DataAbilityPredicates("EMPLOYEE")
<td class="cellrowborder" valign="top" width="69.56%" headers="mcps1.1.3.1.2 "><p id="p158461234133315"><a name="p158461234133315"></a><a name="p158461234133315"></a><strong id="b114291481777"><a name="b114291481777"></a><a name="b114291481777"></a>DataAbilityPredicates</strong> object that groups rows that have the same value.</p>
</td>
</tr>
</tbody>
</table>
- Example
```
let predicates = new dataAbility.DataAbilityPredicates("EMPLOYEE")
<td class="cellrowborder" valign="top" width="61.29%" headers="mcps1.1.5.1.4 "><p id="p654944414119"><a name="p654944414119"></a><a name="p654944414119"></a>Name of the index column.</p>
<td class="cellrowborder" valign="top" width="61.29%" headers="mcps1.1.5.1.4 "><p id="p163145220191"><a name="p163145220191"></a><a name="p163145220191"></a>Column name in the database table.</p>
<td class="cellrowborder" valign="top" width="61.29%" headers="mcps1.1.5.1.4 "><p id="p4140741183519"><a name="p4140741183519"></a><a name="p4140741183519"></a>Column name in the database table.</p>
> The initial APIs of this module are supported since API version 8. Newly added APIs will be marked with a superscript to indicate their earliest API version.
...
...
@@ -17,16 +17,21 @@ import distributedObject from '@ohos.data.distributedDataObject'
Creates a **distributedObject** instance. You can specify the attribute of the instance in **source**. This method returns the **distributedObject** instance created.
Creates a distributed data object.
** System Capability**: SystemCapability.DistributedDataManager.DataObject.DistributedObject
@@ -58,20 +63,29 @@ Creates a session ID randomly.
## DistributedObject
Represents a **distributedObject** instance.
### setSessionId
setSessionId(sessionId?: string): boolean
Sets a session ID for synchronization. Automatic synchronization is performed for multiple devices with the same session ID on a trusted network. To remove a device from the distributed network, set this parameter to "" or leave it unspecified. If **true** is returned, the session ID is set successfully.
Sets a session ID for synchronization. Automatic synchronization is performed for multiple devices with the same session ID on a trusted network.
** System Capability**: SystemCapability.DistributedDataManager.DataObject.DistributedObject
| sessionId | string | No| ID of a distributed object on a trusted network.|
| sessionId | string | No| ID of a distributed data object on a trusted network. To remove a distributed data object from the network, set this parameter to "" or leave it empty.|
**Return Value**
| Type| Description|
| -------- | -------- |
| boolean | Returns **true** if the session ID is set successfully;<br>returns **false** otherwise. |
| type | string | Yes| Event type to subscribe to. The value is **change**, which indicates data change events.|
| callback | Callback<{sessionId:string,fields:Array<string>}> | Yes| Callback used to return the data changes of the distributed object. In the callback, **sessionId** indicates the session ID of the distributed object, and **fields** indicates the attributes of the object.|
| callback | Callback<{sessionId:string,fields:Array<string>}> | Yes| Callback used to return the changes of the distributed data object.<br>**sessionId** indicates the session ID of the distributed data object.<br>**fields** indicates the attributes of the distributed data object changed.|
| type | string | Yes| Event type to unsubscribe from. The value is **change**, which indicates data change events.|
| callback | Callback<{sessionId:string,fields:Array<string>}> | No| Callback used to return changes of the distributed object. If this parameter is not specified, all callbacks related to data changes will be unregistered.|
| type | string | Yes| Event type to subscribe to. The value is **change**, which indicates data change events.|
| callback | Callback<{sessionId:string,fields:Array<string>}> | No| Callback used to return changes of the distributed data object. If this parameter is not specified, all callbacks related to data changes will be unregistered.<br>**sessionId** indicates the session ID of the distributed data object.<br>**fields** indicates the attributes of the distributed data object changed.|
| type | string | Yes| Event type to subscribe to. The value is "status", which indicates the status (online or offline) change events.|
| callback | Callback<{sessionId:string,networkId:string,status:'online'\|'offline'}> | Yes| Callback used to return the status changes of the distributed object. In the callback, **sessionId** indicates the session ID of the distributed object, and **status** indicates the online or offline status of the distributed object.|
| callback | Callback<{sessionId:string,networkId:string,status:'online'\|'offline'}> | Yes| Callback used to return the online or offline status.<br>**sessionId** indicates the session ID of the distributed data object.<br>**networkId** indicates the network ID of the device.<br>**status** indicates the status, which can be online or offline.|
| type | string | Yes| Event type to subscribe to. The value is "status", which indicates the status (online or offline) change events.|
| callback | Callback<{sessionId:string,networkId:string,status:'online'\|'offline'}> | No| Callback used to return the status changes. If this parameter is not specified, all the status change callbacks will be unregistered.|
| callback | Callback<{sessionId:string,deviceId:string,status:'online'\|'offline'}> | No| Callback used to return the status changes. If this parameter is not specified, all the status change callbacks will be unregistered.<br>**sessionId** indicates the session ID of the distributed data object.<br>**deviceId** indicates the device ID of the distributed data object.<br>**status** indicates the status, which can be online or offline.|
> 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.
Obtains a relational database (RDB) store. You can set parameters for the RDB store based on service requirements, call APIs to perform data operations, and use a callback to return the result.
Obtains a relational database (RDB) store. This method uses an asynchronous callback to return the result. You can set parameters for the RDB store based on service requirements and call APIs to perform data operations.
- Parameters
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| context | Context | Yes| Context of the app or functionality.|
| config | [StoreConfig](#storeconfig) | Yes| Configuration of the RDB store.|
| version | number | Yes| RDB store version.|
| callback | AsyncCallback<[RdbStore](#rdbstore)> | Yes| Callback invoked to return the RDB store obtained.|
export default class MainAbility extends Ability {
const STORE_CONFIG = { name: "RdbTest.db"}
const SQL_CREATE_TABLE = "CREATE TABLE IF NOT EXISTS EMPLOYEE (ID INTEGER PRIMARY KEY AUTOINCREMENT, NAME TEXT NOT NULL, AGE INTEGER, SALARY REAL, CODES BLOB)"
data_rdb.getRdbStore(this.context, STORE_CONFIG, 1, function (err, rdbStore) {
rdbStore.executeSql(SQL_CREATE_TABLE)
console.info(TAG + 'create table done.')
})
}
```
**Parameters**
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| context<sup>8+</sup> | Context | Yes| Context of the app or functionality.|
| config | [StoreConfig](#storeconfig) | Yes| Configuration of the RDB store.|
| version | number | Yes| RDB store version.|
| callback | AsyncCallback<[RdbStore](#rdbstore)> | Yes| Callback invoked to return the RDB store obtained.|
**Example**
```
import data_rdb from '@ohos.data.rdb'
const STORE_CONFIG = { name: "RdbTest.db"}
const SQL_CREATE_TABLE = "CREATE TABLE IF NOT EXISTS EMPLOYEE (ID INTEGER PRIMARY KEY AUTOINCREMENT, NAME TEXT NOT NULL, AGE INTEGER, SALARY REAL, CODES BLOB)"
data_rdb.getRdbStore(STORE_CONFIG, 1, function (err, rdbStore) {
rdbStore.executeSql(SQL_CREATE_TABLE)
console.info('create table done.')
})
```
The sample code of API<sup>9</sup> is as follows:
```
import Ability from '@ohos.application.Ability'
import data_rdb from '@ohos.data.rdb'
export default class MainAbility extends Ability {
const STORE_CONFIG = { name: "RdbTest.db"}
const SQL_CREATE_TABLE = "CREATE TABLE IF NOT EXISTS EMPLOYEE (ID INTEGER PRIMARY KEY AUTOINCREMENT, NAME TEXT NOT NULL, AGE INTEGER, SALARY REAL, CODES BLOB)"
data_rdb.getRdbStore(this.context, STORE_CONFIG, 1, function (err, rdbStore) {
Obtains an RDB store. You can set parameters for the RDB store based on service requirements, call APIs to perform data operations, and use a promise to return the result.
Obtains an RDB store. This method uses a promise to return the result. You can set parameters for the RDB store based on service requirements and call APIs to perform data operations.
- Parameters
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| context | Context | Yes| Context of the app or functionality.|
| config | [StoreConfig](#storeconfig) | Yes| Configuration of the RDB store.|
| Promise<[RdbStore](#rdbstore)> | Promise used to return the RDB store obtained.|
**Parameters**
- Example
```
import Ability from '@ohos.application.Ability'
import data_rdb from '@ohos.data.rdb'
export default class MainAbility extends Ability {
const STORE_CONFIG = { name: "RdbTest.db" }
const SQL_CREATE_TABLE = "CREATE TABLE IF NOT EXISTS EMPLOYEE (ID INTEGER PRIMARY KEY AUTOINCREMENT, NAME TEXT NOT NULL, AGE INTEGER, SALARY REAL, CODES BLOB)"
let promise = data_rdb.getRdbStore(this.context, STORE_CONFIG, 1);
promise.then(async (rdbStore) => {
await rdbStore.executeSql(SQL_CREATE_TABLE, null)
}).catch((err) => {
expect(null).assertFail();
})
}
```
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| context<sup>8+</sup> | Context | Yes| Context of the app or functionality.|
| config | [StoreConfig](#storeconfig) | Yes| Configuration of the RDB store.|
| version | number | Yes| RDB store version.|
**Return value**
| Type| Description|
| -------- | -------- |
| Promise<[RdbStore](#rdbstore)> | Promise used to return the RDB store obtained.|
**Example**
```
import data_rdb from '@ohos.data.rdb'
const STORE_CONFIG = { name: "RdbTest.db" }
const SQL_CREATE_TABLE = "CREATE TABLE IF NOT EXISTS EMPLOYEE (ID INTEGER PRIMARY KEY AUTOINCREMENT, NAME TEXT NOT NULL, AGE INTEGER, SALARY REAL, CODES BLOB)"
let promisegetRdb = data_rdb.getRdbStore(STORE_CONFIG, 1);
promisegetRdb.then(async (rdbStore) => {
let promiseExecSql = rdbStore.executeSql(SQL_CREATE_TABLE, null)
promiseExecSql.then(() => {
console.info('executeSql creat done.')
}).catch((err) => {
console.log("executeSql creat err.")
})
}).catch((err) => {
console.log("getRdbStore err.")
})
```
The sample code of API<sup>9</sup> is as follows:
```
import Ability from '@ohos.application.Ability'
import data_rdb from '@ohos.data.rdb'
export default class MainAbility extends Ability {
const STORE_CONFIG = { name: "RdbTest.db" }
const SQL_CREATE_TABLE = "CREATE TABLE IF NOT EXISTS EMPLOYEE (ID INTEGER PRIMARY KEY AUTOINCREMENT, NAME TEXT NOT NULL, AGE INTEGER, SALARY REAL, CODES BLOB)"
let promisegetRdb = data_rdb.getRdbStore(this.context, STORE_CONFIG, 1);
promisegetRdb.then(async (rdbStore) => {
let promiseExecSql = rdbStore.executeSql(SQL_CREATE_TABLE, null)
Deletes an RDB store. This method uses a callback to return the result.
- Parameters
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| context | Context | Yes| Context of the app or functionality.|
| name | string | Yes| Name of the RDB store to delete.|
| callback | AsyncCallback<void> | Yes| Callback invoked to return the result. If the RDB store is deleted, **true** will be returned. Otherwise, **false** will be returned.|
| Promise<void> | Promise used to return the result. If the RDB store is deleted, **true** will be returned. Otherwise, **false** will be returned.|
**Parameters**
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| context<sup>8+</sup> | Context | Yes| Context of the app or functionality.|
| name | string | Yes| Name of the RDB store to delete.|
- Example
**Return value**
| Type| Description|
| -------- | -------- |
| Promise<void> | Promise used to return the result.|
**Example**
```
import Ability from '@ohos.application.Ability'
import data_rdb from '@ohos.data.rdb'
export default class MainAbility extends Ability {
let promise = data_rdb.deleteRdbStore(this.context, "RdbTest.db")
promise.then(()=>{
console.info(TAG + 'delete store done.')
})
}
let promisedeleteRdb = data_rdb.deleteRdbStore("RdbTest.db")
promisedeleteRdb.then(()=>{
console.info('delete store done.')
}).catch((err) => {
console.log("deleteRdbStore err.")
})
```
The sample code of API<sup>9</sup> is as follows:
```
import Ability from '@ohos.application.Ability'
import data_rdb from '@ohos.data.rdb'
export default class MainAbility extends Ability {
let promisedeleteRdb = data_rdb.deleteRdbStore(this.context, "RdbTest.db")
promisedeleteRdb.then(()=>{
console.info('delete store done.')
}).catch((err) => {
console.log("deleteRdbStore err.")
})
}
```
## RdbPredicates
Defines predicates for an RDB store. This class determines whether the conditional expression for the RDB store is true or false.
...
...
@@ -142,55 +210,58 @@ constructor(name: string)
A constructor used to create an **RdbPredicates** object.
| field | string | Yes| Column name in the database table.|
| value | string | Yes| Value to match the **RdbPredicates**. <br>Wildcards are supported. ***** indicates zero, one, or multiple digits or characters. **?** indicates a single digit or character.|
**Parameters**
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| field | string | Yes| Column name in the database table.|
| value | string | Yes| Value to match the **RdbPredicates**.<br><br>Wildcards are supported. ***** indicates zero, one, or multiple digits or characters. **?** indicates a single digit or character.|
- Return value
| Type| Description|
| -------- | -------- |
| [RdbPredicates](#rdbpredicates) | **RdbPredicates** object that matches the specified field.|
**Return value**
| Type| Description|
| -------- | -------- |
| [RdbPredicates](#rdbpredicates) | **RdbPredicates** object that matches the specified field.|
- Example
**Example**
```
let predicates = new data_rdb.RdbPredicates("EMPLOYEE")
Inserts a row of data into a table. This method uses a callback to return the result.
- Parameters
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| name | string | Yes| Name of the target table.|
| values | [ValuesBucket](#valuesbucket) | Yes| Row of data to insert.|
| callback | AsyncCallback<number> | Yes| Callback invoked to return the result. If the operation is successful, the row ID will be returned. Otherwise, **-1** will be returned.|
| values | [ValuesBucket](#valuesbucket) | Yes| Row of data to insert.|
| callback | AsyncCallback<number> | Yes| Callback invoked to return the result. If the operation is successful, the row ID will be returned. Otherwise, **-1** will be returned.|
**Example**
```
const valueBucket = {
"NAME": "Lisa",
...
...
@@ -936,8 +1041,8 @@ Inserts a row of data into a table. This method uses a callback to return the re
"CODES": new Uint8Array([1, 2, 3, 4, 5]),
}
rdbStore.insert("EMPLOYEE", valueBucket, function (err, ret) {
| Promise<number> | Promise used to return the result. If the operation is successful, the row ID will be returned. Otherwise, **-1** will be returned.|
**Parameters**
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| name | string | Yes| Name of the target table.|
| values | [ValuesBucket](#valuesbucket) | Yes| Row of data to insert.|
- Example
**Return value**
| Type| Description|
| -------- | -------- |
| Promise<number> | Promise used to return the result. If the operation is successful, the row ID will be returned. Otherwise, **-1** will be returned.|
**Example**
```
const valueBucket = {
"NAME": "Lisa",
...
...
@@ -966,10 +1073,12 @@ Inserts a row of data into a table. This method uses a promise to return the res
"SALARY": 100.5,
"CODES": new Uint8Array([1, 2, 3, 4, 5]),
}
let promise = rdbStore.insert("EMPLOYEE", valueBucket)
promise.then(async (ret) => {
await console.log(TAG + "insert first done: " + ret)
}).catch((err) => {})
let promiseinsert = rdbStore.insert("EMPLOYEE", valueBucket)
Updates data in the database based on the specified RdbPredicates object. This method uses a callback to return the result.
- Parameters
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| values | [ValuesBucket](#valuesbucket) | Yes| Data to update. The value specifies the row of data to be updated in the database. The key-value pair is associated with the column name in the target table.|
| rdbPredicates | [RdbPredicates](#rdbpredicates) | Yes| Row of data to insert.|
| callback | AsyncCallback<number> | Yes| Callback invoked to return the number of rows updated.|
| values | [ValuesBucket](#valuesbucket) | Yes| Data to update. The value specifies the row of data to be updated in the database. The key-value pair is associated with the column name in the target table.|
| rdbPredicates | [RdbPredicates](#rdbpredicates) | Yes| Row of data to insert.|
| callback | AsyncCallback<number> | Yes| Callback used to return the number of rows updated.|
**Example**
```
const valueBucket = {
"NAME": "Rose",
...
...
@@ -997,7 +1108,7 @@ Updates data in the database based on the specified RdbPredicates object. This m
let predicates = new data_rdb.RdbPredicates("EMPLOYEE")
predicates.equalTo("NAME", "Lisa")
rdbStore.update(valueBucket, predicates, function (err, ret) {
Updates data in the database based on the specified RdbPredicates object. This method uses a promise to return the result.
- Parameters
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| values | [ValuesBucket](#valuesbucket) | Yes| Data to update. The value specifies the row of data to be updated in the database. The key-value pair is associated with the column name in the target table.|
| rdbPredicates | [RdbPredicates](#rdbpredicates) | Yes| Row of data to insert.|
| Promise<number> | Promise used to return the number of rows updated.|
**Parameters**
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| values | [ValuesBucket](#valuesbucket) | Yes| Data to update. The value specifies the row of data to be updated in the database. The key-value pair is associated with the column name in the target table.|
| rdbPredicates | [RdbPredicates](#rdbpredicates) | Yes| Row of data to insert.|
- Example
**Return value**
| Type| Description|
| -------- | -------- |
| Promise<number> | Promise used to return the number of rows updated.|
**Example**
```
const valueBucket = {
"NAME": "Rose",
...
...
@@ -1028,10 +1141,12 @@ Updates data in the database based on the specified RdbPredicates object. This m
}
let predicates = new data_rdb.RdbPredicates("EMPLOYEE")
predicates.equalTo("NAME", "Lisa")
let promise = rdbStore.update(valueBucket, predicates)
Queries data in the database based on specified conditions. This method uses a callback to return the result.
- Parameters
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| rdbPredicates | [RdbPredicates](#rdbpredicates) | Yes| Query conditions specified by the **RdbPredicates** object.|
| columns | Array<string> | Yes| Columns to query. If this parameter is not specified, the query applies to all columns.|
| callback | AsyncCallback<[ResultSet](js-apis-data-resultset.md)> | Yes| Callback invoked to return the result. If the operation is successful, a **ResultSet** object will be returned.|
| rdbPredicates | [RdbPredicates](#rdbpredicates) | Yes| Query conditions specified by the **RdbPredicates** object.|
| columns | Array<string> | Yes| Columns to query. If this parameter is not specified, the query applies to all columns.|
| callback | AsyncCallback<[ResultSet](js-apis-data-resultset.md)> | Yes| Callback invoked to return the result. If the operation is successful, a **ResultSet** object will be returned.|
**Example**
```
let predicates = new data_rdb.RdbPredicates("EMPLOYEE")
predicates.equalTo("NAME", "Rose")
rdbStore.query(predicates, ["ID", "NAME", "AGE", "SALARY", "CODES"], function (err, resultSet) {
| Promise<[ResultSet](../apis/js-apis-data-resultset.md)> | Promise used to return the result. If the operation is successful, a **ResultSet** object will be returned.|
**Parameters**
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| rdbPredicates | [RdbPredicates](#rdbpredicates) | Yes| Query conditions specified by the **RdbPredicates** object.|
| columns | Array<string> | No| Columns to query. If this parameter is not specified, the query applies to all columns.|
- Example
**Return value**
| Type| Description|
| -------- | -------- |
| Promise<[ResultSet](../apis/js-apis-data-resultset.md)> | Promise used to return the result. If the operation is successful, a **ResultSet** object will be returned.|
**Example**
```
let predicates = new data_rdb.RdbPredicates("EMPLOYEE")
predicates.equalTo("NAME", "Rose")
let promise = rdbStore.query(predicates, ["ID", "NAME", "AGE", "SALARY", "CODES"])
Queries data in the RDB store using the specified SQL statement. This method uses a callback to return the result.
- Parameters
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| sql | string | Yes| SQL statement to run.|
| bindArgs | Array<[ValueType](#valuetype)> | Yes| Values of the parameters in the SQL statement.|
| callback | AsyncCallback<[ResultSet](js-apis-data-resultset.md)> | Yes| Callback invoked to return the result. If the operation is successful, a **ResultSet** object will be returned.|
| bindArgs | Array<[ValueType](#valuetype)> | Yes| Values of the parameters in the SQL statement.|
| callback | AsyncCallback<[ResultSet](js-apis-data-resultset.md)> | Yes| Callback invoked to return the result. If the operation is successful, a **ResultSet** object will be returned.|
**Example**
```
rdbStore.querySql("SELECT * FROM EMPLOYEE CROSS JOIN BOOK WHERE BOOK.NAME = ?", ['sanguo'], function (err, resultSet) {
| Promise<[ResultSet](../apis/js-apis-data-resultset.md)> | Promise used to return the result. If the operation is successful, a **ResultSet** object will be returned.|
**Parameters**
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| sql | string | Yes| SQL statement to run.|
| bindArgs | Array<[ValueType](#valuetype)> | No| Values of the parameters in the SQL statement.|
- Example
**Return value**
| Type| Description|
| -------- | -------- |
| Promise<[ResultSet](../apis/js-apis-data-resultset.md)> | Promise used to return the result. If the operation is successful, a **ResultSet** object will be returned.|
**Example**
```
let promise = rdbStore.querySql("SELECT * FROM EMPLOYEE CROSS JOIN BOOK WHERE BOOK.NAME = ?", ['sanguo'])
Obtains the distributed table name for a remote device based on the local table name. The distributed table name is required when the database of a remote device is queried. This method uses a callback to return the result.
- Parameters
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| device | string | Yes| Remote device.|
| table | string | Yes| Local table name.|
| callback | AsyncCallback<string> | Yes| Callback invoked to return the result. If the operation succeeds, the distributed table name of the remote device is returned.|
| callback | AsyncCallback<string> | Yes| Callback invoked to return the result. If the operation succeeds, the distributed table name of the remote device is returned.|
**Example**
```
rdbStore.obtainDistributedTableName(deviceId, "EMPLOYEE", function (err, tableName) {
if (err) {
...
...
@@ -1302,47 +1531,51 @@ Obtains the distributed table name for a remote device based on the local table
Obtains the distributed table name for a remote device based on the local table name. The distributed table name is required when the database of a remote device is queried. This method uses a promise to return the result.
Synchronizes data between devices. This method uses a callback to return the result.
- Parameters
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| mode | SyncMode | Yes| Data synchronization mode, which can be **push** or **pull**.|
| predicates | RdbPredicates | Yes| **RdbPredicates** object that specifies the data and devices to synchronize.|
| callback | AsyncCallback<Array<[string,number]>> | Yes| Callback invoked to send the synchronization result to the caller. <br>**string** indicates the device ID. <br>**number** indicates the synchronization status of each device. The value **0** indicates a successful synchronization. Other values indicate a synchronization failure. |
| mode | [SyncMode](#syncmode8) | Yes| Data synchronization mode. The value can be **push** or **pull**.|
| predicates | [RdbPredicates](#rdbpredicates) | Yes| **RdbPredicates** object that specifies the data and devices to synchronize.|
| callback | AsyncCallback<Array<[string, number]>> | Yes| Callback invoked to send the synchronization result to the caller. <br>**string** indicates the device ID. <br>**number** indicates the synchronization status of each device. The value **0** indicates a successful synchronization. Other values indicate a synchronization failure. |
**Example**
```
let predicate = new rdb.RdbPredicates('EMPLOYEE')
predicate.inDevices(['12345678abcde'])
...
...
@@ -1359,77 +1592,89 @@ Synchronizes data between devices. This method uses a callback to return the res
| Promise<Array<[string,number]>> | Promise used to return the synchronization result to the caller. <br>**string** indicates the device ID. <br>**number** indicates the synchronization status of each device. The value **0** indicates a successful synchronization. Other values indicate a synchronization failure. |
**Parameters**
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| mode | [SyncMode](#syncmode8) | Yes| Data synchronization mode. The value can be **push** or **pull**.|
| predicates | [RdbPredicates](#rdbpredicates) | Yes| **RdbPredicates** object that specifies the data and devices to synchronize.|
- Example
**Return value**
| Type| Description|
| -------- | -------- |
| Promise<Array<[string, number]>> | Promise used to return the synchronization result to the caller. <br>**string** indicates the device ID. <br>**number** indicates the synchronization status of each device. The value **0** indicates a successful synchronization. Other values indicate a synchronization failure. |
**Example**
```
let predicate = new rdb.RdbPredicates('EMPLOYEE')
predicate.inDevices(['12345678abcde'])
let promise = rdbStore.sync(rdb.SyncMode.SYNC_MODE_PUSH, predicate)
promise.then(result) {
let predicatesync = new data_rdb.RdbPredicates('EMPLOYEE')
predicatesync.inDevices(['12345678abcde'])
let promisesync = rdbStore.sync(data_rdb.SyncMode.SYNC_MODE_PUSH, predicatesync)
>The initial APIs of this module are supported since API version 7. Newly added APIs will be marked with a superscript to indicate their earliest API version.
> The 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.
<tdclass="cellrowborder"valign="top"width="59.245924592459254%"headers="mcps1.1.5.1.4 "><pid="p1149515020434"><aname="p1149515020434"></a><aname="p1149515020434"></a>Names of all columns in the result set.</p>
<tdclass="cellrowborder"valign="top"width="59.245924592459254%"headers="mcps1.1.5.1.4 "><pid="p114957010437"><aname="p114957010437"></a><aname="p114957010437"></a>Number of columns in the result set.</p>
<tdclass="cellrowborder"valign="top"width="59.245924592459254%"headers="mcps1.1.5.1.4 "><pid="p849720184311"><aname="p849720184311"></a><aname="p849720184311"></a>Number of rows in the result set.</p>
<tdclass="cellrowborder"valign="top"width="59.245924592459254%"headers="mcps1.1.5.1.4 "><pid="p1149840134313"><aname="p1149840134313"></a><aname="p1149840134313"></a>Index of the current row in the result set.</p>
<tdclass="cellrowborder"valign="top"width="59.245924592459254%"headers="mcps1.1.5.1.4 "><pid="p54998044315"><aname="p54998044315"></a><aname="p54998044315"></a>Specifies whether the cursor is in the first row of the result set.</p>
<tdclass="cellrowborder"valign="top"width="59.245924592459254%"headers="mcps1.1.5.1.4 "><pid="p1950010017432"><aname="p1950010017432"></a><aname="p1950010017432"></a>Whether the cursor is in the last row of the result set.</p>
<tdclass="cellrowborder"valign="top"width="59.245924592459254%"headers="mcps1.1.5.1.4 "><pid="p1650013017433"><aname="p1650013017433"></a><aname="p1650013017433"></a>Whether the cursor is after the last row of the result set.</p>
<tdclass="cellrowborder"valign="top"width="59.245924592459254%"headers="mcps1.1.5.1.4 "><pid="p1834523310411"><aname="p1834523310411"></a><aname="p1834523310411"></a>Whether the cursor has been moved.</p>
<tdclass="cellrowborder"valign="top"width="59.245924592459254%"headers="mcps1.1.5.1.4 "><pid="p35031016433"><aname="p35031016433"></a><aname="p35031016433"></a>Whether the result set is closed.</p>
<td class="cellrowborder" valign="top" width="61.29%" headers="mcps1.1.5.1.4 "><p id="p154152015121913"><a name="p154152015121913"></a><a name="p154152015121913"></a>Offset relative to the current position.</p>
<td class="cellrowborder" valign="top" width="61.29%" headers="mcps1.1.5.1.4 "><p id="p1690919394126"><a name="p1690919394126"></a><a name="p1690919394126"></a>Position to which the cursor is to be moved.</p>
<td class="cellrowborder" valign="top" width="82.99%" headers="mcps1.1.3.1.2 "><p id="p155414347169"><a name="p155414347169"></a><a name="p155414347169"></a>Value in the specified column as a byte array.</p>
<td class="cellrowborder" valign="top" width="82.99%" headers="mcps1.1.3.1.2 "><p id="p3871251119"><a name="p3871251119"></a><a name="p3871251119"></a>Value in the specified column as a string.</p>
</td>
</tr>
</tbody>
</table>
- Example
```
const name = resultSet.getString(resultSet.getColumnIndex("NAME"))
```
### getLong<a name="section270062312014"></a>
getLong\(columnIndex: number\): number
Obtains the value in the specified column in the current row as a **Long**.
<td class="cellrowborder" valign="top" width="82.99%" headers="mcps1.1.3.1.2 "><p id="p1870622302018"><a name="p1870622302018"></a><a name="p1870622302018"></a>Value in the specified column as a <strong id="b15869112345117"><a name="b15869112345117"></a><a name="b15869112345117"></a>Long</strong>.</p>
</td>
</tr>
</tbody>
</table>
- Example
```
const age = resultSet.getLong(resultSet.getColumnIndex("AGE"))
```
### getDouble<a name="section3820153618207"></a>
getDouble\(columnIndex: number\): number
Obtains the value in the specified column in the current row as a **double**.
<td class="cellrowborder" valign="top" width="82.99%" headers="mcps1.1.3.1.2 "><p id="p982423642015"><a name="p982423642015"></a><a name="p982423642015"></a>Value in the specified column as a <strong id="b1396205911447"><a name="b1396205911447"></a><a name="b1396205911447"></a>double</strong>.</p>
> The initial APIs of this module are supported since API version 6. Newly added APIs will be marked with a superscript to indicate their earliest API version. <br/>The APIs of this module are no longer maintained since API Version 9. You are advised to use [@ohos.data.preferences](js-apis-data-preferences.md).
>
> - The initial APIs of this module are supported since API version 6. Newly added APIs will be marked with a superscript to indicate their earliest API version.
>
> - The APIs of this module are no longer maintained since API Version 9. You are advised to use [`@ohos.data.preferences`](js-apis-data-preferences.md).
## Modules to Import
...
...
@@ -45,12 +48,18 @@ Reads a file and loads the data to the **Storage** instance in synchronous mode.
```
import dataStorage from '@ohos.data.storage'
import featureAbility from '@ohos.ability.featureAbility'
var context = featureAbility.getContext()
var path = await context.getFilesDir()
let storage = dataStorage.getStorageSync(path + '/mystore')
Removes the singleton **Storage** instance of a file from the cache. The removed instance cannot be used for data operations. Otherwise, data inconsistency will occur.
This method uses a promise to return the result.
This method uses an asynchronous callback to return the result.
Obtains the **Storage** instance corresponding to the specified file, writes data to the **Storage** instance using a **Storage** API, and saves the modification using **flush()** or **flushSync()**.
This method uses a promise to return the result.
This method uses an asynchronous callback to return the result.
