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!17992 [翻译完成】PR17296 

Merge pull request !17992 from Annie_wang/PR17296
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en/application-dev/database/data-persistence-by-kv-store.md
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......@@ -21,22 +21,24 @@ The key-value (KV) database stores data in the form of KV pairs. You can use KV
The following table lists the APIs used for KV data persistence. Most of the APIs are executed asynchronously, using a callback or promise to return the result. The following table uses the callback-based APIs as an example. For more information about the APIs, see [Distributed KV Store](../reference/apis/js-apis-distributedKVStore.md).
| API| Description|
| API| Description|
| -------- | -------- |
| createKVManager(config: KVManagerConfig): KVManager | Creates a **KvManager** instance to manage database objects.|
| getKVStore<T>(storeId: string, options: Options, callback: AsyncCallback<T>): void | Creates and obtains a KV store of the specified type.|
| put(key: string, value: Uint8Array\|string\|number\|boolean, callback: AsyncCallback<void>): void | Adds a KV pair of the specified type to this KV store.|
| get(key: string, callback: AsyncCallback<Uint8Array\|string\|boolean\|number>): void | Obtains the value of the specified key.|
| delete(key: string, callback: AsyncCallback<void>): void | Deletes a KV pair based on the specified key.|
| createKVManager(config: KVManagerConfig): KVManager | Creates a **KvManager** instance to manage database objects.|
| getKVStore<T>(storeId: string, options: Options, callback: AsyncCallback<T>): void | Creates and obtains a KV store of the specified type.|
| put(key: string, value: Uint8Array\|string\|number\|boolean, callback: AsyncCallback<void>): void | Adds a KV pair of the specified type to this KV store.|
| get(key: string, callback: AsyncCallback<Uint8Array\|string\|boolean\|number>): void | Obtains the value of the specified key.|
| delete(key: string, callback: AsyncCallback<void>): void | Deletes a KV pair based on the specified key.|
## How to Develop
1. Create a **KvManager** instance to manage database objects. Example:
1. Create a **KvManager** instance to manage database objects.
Example:
Stage model:
```js
// Import the module.
import distributedKVStore from '@ohos.data.distributedKVStore';
......@@ -67,7 +69,7 @@ The following table lists the APIs used for KV data persistence. Most of the API
FA model:
```js
// Import the module.
import distributedKVStore from '@ohos.data.distributedKVStore';
......@@ -90,8 +92,10 @@ The following table lists the APIs used for KV data persistence. Most of the API
}
```
2. Create and obtain a KV store. Example:
2. Create and obtain a KV store.
Example:
```js
try {
const options = {
......@@ -116,8 +120,10 @@ The following table lists the APIs used for KV data persistence. Most of the API
}
```
3. Use **put()** to add data to the KV store. Example:
3. Use **put()** to add data to the KV store.
Example:
```js
const KEY_TEST_STRING_ELEMENT = 'key_test_string';
const VALUE_TEST_STRING_ELEMENT = 'value_test_string';
......@@ -138,8 +144,10 @@ The following table lists the APIs used for KV data persistence. Most of the API
>
> The **put()** method adds a KV pair if the specified key does not exists and changes the value if the the specified key already exists.
4. Use **get()** to obtain the value of a key. Example:
4. Use **get()** to obtain the value of a key.
Example:
```js
const KEY_TEST_STRING_ELEMENT = 'key_test_string';
const VALUE_TEST_STRING_ELEMENT = 'value_test_string';
......@@ -163,8 +171,10 @@ The following table lists the APIs used for KV data persistence. Most of the API
}
```
5. Use **delete()** to delete the data of the specified key. Example:
5. Use **delete()** to delete the data of the specified key.
Example:
```js
const KEY_TEST_STRING_ELEMENT = 'key_test_string';
const VALUE_TEST_STRING_ELEMENT = 'value_test_string';
......
en/application-dev/database/data-persistence-by-preferences.md
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......@@ -30,23 +30,23 @@ The preference persistent file of an application is stored in the application sa
The following table lists the APIs used for preferences data persistence. Most of the APIs are executed asynchronously, using a callback or promise to return the result. The following table uses the callback-based APIs as an example. For more information about the APIs, see [User Preferences](../reference/apis/js-apis-data-preferences.md).
| API| Description|
| API| Description|
| -------- | -------- |
| getPreferences(context: Context, name: string, callback: AsyncCallback<Preferences>): void | Obtain a **Preferences** instance.|
| put(key: string, value: ValueType, callback: AsyncCallback<void>): void | Writes data to the Preferences instance. You can use **flush()** to persist the **Preferences** instance data.|
| has(key: string, callback: AsyncCallback<boolean>): void | Checks whether the **Preferences** instance contains a KV pair with the given key. The key cannot be empty.|
| get(key: string, defValue: ValueType, callback: AsyncCallback<ValueType>): void | Obtains the value of the specified key. If the value is null or not of the default value type, **defValue** is returned.|
| delete(key: string, callback: AsyncCallback<void>): void | Deletes the KV pair with the given key from the **Preferences** instance.|
| flush(callback: AsyncCallback<void>): void | Flushes the data of this **Preferences** instance to a file for data persistence.|
| on(type: 'change', callback: Callback<{ key : string }>): void | Subscribes to data changes of the specified key. When the value of the specified key is changed and saved by **flush()**, a callback will be invoked to return the new data.|
| off(type: 'change', callback?: Callback<{ key : string }>): void | Unsubscribes from data changes.|
| deletePreferences(context: Context, name: string, callback: AsyncCallback<void>): void | Deletes a **Preferences** instance from memory. If the **Preferences** instance has a persistent file, this API also deletes the persistent file.|
| getPreferences(context: Context, name: string, callback: AsyncCallback<Preferences>): void | Obtain a **Preferences** instance.|
| put(key: string, value: ValueType, callback: AsyncCallback<void>): void | Writes data to the Preferences instance. You can use **flush()** to persist the **Preferences** instance data.|
| has(key: string, callback: AsyncCallback<boolean>): void | Checks whether the **Preferences** instance contains a KV pair with the given key. The key cannot be empty.|
| get(key: string, defValue: ValueType, callback: AsyncCallback<ValueType>): void | Obtains the value of the specified key. If the value is null or not of the default value type, **defValue** is returned.|
| delete(key: string, callback: AsyncCallback<void>): void | Deletes the KV pair with the given key from the **Preferences** instance.|
| flush(callback: AsyncCallback<void>): void | Flushes the data of this **Preferences** instance to a file for data persistence.|
| on(type: 'change', callback: Callback<{ key : string }>): void | Subscribes to data changes of the specified key. When the value of the specified key is changed and saved by **flush()**, a callback will be invoked to return the new data.|
| off(type: 'change', callback?: Callback<{ key : string }>): void | Unsubscribes from data changes.|
| deletePreferences(context: Context, name: string, callback: AsyncCallback<void>): void | Deletes a **Preferences** instance from memory. If the **Preferences** instance has a persistent file, this API also deletes the persistent file.|
## How to Develop
1. Import the **@ohos.data.preferences** module.
```js
import dataPreferences from '@ohos.data.preferences';
```
......@@ -55,7 +55,7 @@ The following table lists the APIs used for preferences data persistence. Most o
Stage model:
```js
import UIAbility from '@ohos.app.ability.UIAbility';
......@@ -79,7 +79,7 @@ The following table lists the APIs used for preferences data persistence. Most o
FA model:
```js
import featureAbility from '@ohos.ability.featureAbility';
......@@ -110,7 +110,7 @@ The following table lists the APIs used for preferences data persistence. Most o
Example:
```js
try {
preferences.has('startup', function (err, val) {
......@@ -143,8 +143,10 @@ The following table lists the APIs used for preferences data persistence. Most o
4. Read data.
Use **get()** to obtain the value of the specified key. If the value is null or is not of the default value type, the default data is returned. Example:
Use **get()** to obtain the value of the specified key. If the value is null or is not of the default value type, the default data is returned.
Example:
```js
try {
preferences.get('startup', 'default', (err, val) => {
......@@ -159,11 +161,11 @@ The following table lists the APIs used for preferences data persistence. Most o
}
```
5. Deletes data.
5. Delete data.
Use delete() to delete a KV pair.<br>Example:
```js
try {
preferences.delete('startup', (err) => {
......@@ -234,7 +236,7 @@ The following table lists the APIs used for preferences data persistence. Most o
Example:
```js
try {
dataPreferences.deletePreferences(this.context, 'mystore', (err, val) => {
......
en/application-dev/database/data-persistence-by-rdb-store.md
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......@@ -18,7 +18,7 @@ A relational database (RDB) store is used to store data in complex relational mo
**RelationalStore** provides APIs for applications to perform data operations. With SQLite as the underlying persistent storage engine, **RelationalStore** provides SQLite database features, including transactions, indexes, views, triggers, foreign keys, parameterized queries, prepared SQL statements, and more.
**Figure 1** Working mechanism
![relationStore_local](figures/relationStore_local.jpg)
......@@ -37,15 +37,15 @@ A relational database (RDB) store is used to store data in complex relational mo
The following table lists the APIs used for RDB data persistence. Most of the APIs are executed asynchronously, using a callback or promise to return the result. The following table uses the callback-based APIs as an example. For more information about the APIs, see [RDB Store](../reference/apis/js-apis-data-relationalStore.md).
| API| Description|
| API| Description|
| -------- | -------- |
| getRdbStore(context: Context, config: StoreConfig, callback: AsyncCallback&lt;RdbStore&gt;): void | Obtains a **RdbStore** instance to implement RDB store operations. You can set **RdbStore** parameters based on actual requirements and use **RdbStore** APIs to perform data operations.|
| executeSql(sql: string, bindArgs: Array&lt;ValueType&gt;, callback: AsyncCallback&lt;void&gt;):void | Executes an SQL statement that contains specified arguments but returns no value.|
| insert(table: string, values: ValuesBucket, callback: AsyncCallback&lt;number&gt;):void | Inserts a row of data into a table.|
| update(values: ValuesBucket, predicates: RdbPredicates, callback: AsyncCallback&lt;number&gt;):void | Updates data in the RDB store based on the specified **RdbPredicates** instance.|
| delete(predicates: RdbPredicates, callback: AsyncCallback&lt;number&gt;):void | Deletes data from the RDB store based on the specified **RdbPredicates** instance.|
| query(predicates: RdbPredicates, columns: Array&lt;string&gt;, callback: AsyncCallback&lt;ResultSet&gt;):void | Queries data in the RDB store based on specified conditions.|
| deleteRdbStore(context: Context, name: string, callback: AsyncCallback&lt;void&gt;): void | Deletes an RDB store.|
| getRdbStore(context: Context, config: StoreConfig, callback: AsyncCallback&lt;RdbStore&gt;): void | Obtains a **RdbStore** instance to implement RDB store operations. You can set **RdbStore** parameters based on actual requirements and use **RdbStore** APIs to perform data operations.|
| executeSql(sql: string, bindArgs: Array&lt;ValueType&gt;, callback: AsyncCallback&lt;void&gt;):void | Executes an SQL statement that contains specified arguments but returns no value.|
| insert(table: string, values: ValuesBucket, callback: AsyncCallback&lt;number&gt;):void | Inserts a row of data into a table.|
| update(values: ValuesBucket, predicates: RdbPredicates, callback: AsyncCallback&lt;number&gt;):void | Updates data in the RDB store based on the specified **RdbPredicates** instance.|
| delete(predicates: RdbPredicates, callback: AsyncCallback&lt;number&gt;):void | Deletes data from the RDB store based on the specified **RdbPredicates** instance.|
| query(predicates: RdbPredicates, columns: Array&lt;string&gt;, callback: AsyncCallback&lt;ResultSet&gt;):void | Queries data in the RDB store based on specified conditions.|
| deleteRdbStore(context: Context, name: string, callback: AsyncCallback&lt;void&gt;): void | Deletes an RDB store.|
## How to Develop
......@@ -53,7 +53,7 @@ The following table lists the APIs used for RDB data persistence. Most of the AP
1. Obtain an **RdbStore** instance.<br> Example:
Stage model:
```js
import relationalStore from '@ohos.data.relationalStore'; // Import the module.
import UIAbility from '@ohos.app.ability.UIAbility';
......@@ -84,7 +84,7 @@ The following table lists the APIs used for RDB data persistence. Most of the AP
FA model:
```js
import relationalStore from '@ohos.data.relationalStore'; // Import the module.
import featureAbility from '@ohos.ability.featureAbility';
......@@ -118,8 +118,10 @@ The following table lists the APIs used for RDB data persistence. Most of the AP
>
> - When an application calls **getRdbStore()** to obtain an RDB store instance for the first time, the corresponding database file is generated in the application sandbox. If you want to move the files of an RDB store to another place for view, you must also move the temporary files with finename extensions **-wal** or **-shm** in the same directory. Once an application is uninstalled, the database files and temporary files generated by the application on the device are also removed.
2. Use **insert()** to insert data to the RDB store. Example:
2. Use **insert()** to insert data to the RDB store.
Example:
```js
const valueBucket = {
'NAME': 'Lisa',
......@@ -133,17 +135,19 @@ The following table lists the APIs used for RDB data persistence. Most of the AP
return;
}
console.info(`Succeeded in inserting data. rowId:${rowId}`);
})
})
```
> **NOTE**
>
>
> **RelationalStore** does not provide explicit flush operations for data persistence. Data inserted by **insert()** is stored in files persistently.
3. Modify or delete data based on the specified **Predicates** instance.
Use **update()** to modify data and **delete()** to delete data. Example:
Use **update()** to modify data and **delete()** to delete data.
Example:
```js
// Modify data.
const valueBucket = {
......@@ -176,8 +180,10 @@ The following table lists the APIs used for RDB data persistence. Most of the AP
4. Query data based on the conditions specified by **Predicates**.
Use **query()** to query data. The data obtained is returned in a **ResultSet** object. Example:
Use **query()** to query data. The data obtained is returned in a **ResultSet** object.
Example:
```js
let predicates = new relationalStore.RdbPredicates('EMPLOYEE');
predicates.equalTo('NAME', 'Rose');
......@@ -197,11 +203,13 @@ The following table lists the APIs used for RDB data persistence. Most of the AP
5. Delete the RDB store.
Use **deleteRdbStore()** to delete the RDB store and related database files. Example:
Use **deleteRdbStore()** to delete the RDB store and related database files.
Example:
Stage model:
```js
import UIAbility from '@ohos.app.ability.UIAbility';
......@@ -220,7 +228,7 @@ The following table lists the APIs used for RDB data persistence. Most of the AP
FA model:
```js
import featureAbility from '@ohos.ability.featureAbility';
......
en/application-dev/database/data-sync-of-kv-store.md
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......@@ -79,19 +79,19 @@ When data is added, deleted, or modified, a notification is sent to the subscrib
The following table lists the APIs for cross-device data synchronization of the single KV store. Most of the APIs are executed asynchronously, using a callback or promise to return the result. The following table uses the callback-based APIs as an example. For more information about the APIs, see [Distributed KV Store](../reference/apis/js-apis-distributedKVStore.md).
| API| Description|
| API| Description|
| -------- | -------- |
| createKVManager(config: KVManagerConfig): KVManager | Creates a **KvManager** instance to manage database objects.|
| getKVStore&lt;T&gt;(storeId: string, options: Options, callback: AsyncCallback&lt;T&gt;): void | Creates and obtains a KV store of the specified type.|
| put(key: string, value: Uint8Array\|string\|number\|boolean, callback: AsyncCallback&lt;void&gt;): void | Inserts and updates data.|
| on(event: 'dataChange', type: SubscribeType, listener: Callback&lt;ChangeNotification&gt;): void | Subscribes to data changes in the KV store.|
| get(key: string, callback: AsyncCallback&lt;boolean \| string \| number \| Uint8Array&gt;): void | Queries the value of the specified key.|
| sync(deviceIds: string[], mode: SyncMode, delayMs?: number): void | Triggers a manual synchronization of the KV store.|
| createKVManager(config: KVManagerConfig): KVManager | Creates a **KvManager** instance to manage database objects.|
| getKVStore&lt;T&gt;(storeId: string, options: Options, callback: AsyncCallback&lt;T&gt;): void | Creates and obtains a KV store of the specified type.|
| put(key: string, value: Uint8Array\|string\|number\|boolean, callback: AsyncCallback&lt;void&gt;): void | Inserts and updates data.|
| on(event: 'dataChange', type: SubscribeType, listener: Callback&lt;ChangeNotification&gt;): void | Subscribes to data changes in the KV store.|
| get(key: string, callback: AsyncCallback&lt;boolean \| string \| number \| Uint8Array&gt;): void | Queries the value of the specified key.|
| sync(deviceIds: string[], mode: SyncMode, delayMs?: number): void | Triggers a manual synchronization of the KV store.|
## How to Develop
The following uses a single KV store as an example to describe how to implement cross-device data synchronization. The following describes the development process.
The following uses a single KV store as an example to describe how to implement cross-device data synchronization. The development process is as follows.
![kvStore_development_process](figures/kvStore_development_process.png)
......@@ -100,7 +100,7 @@ The following uses a single KV store as an example to describe how to implement
> The data on a device can be synchronized only to the devices whose data security labels are not higher than the security level of the device. For details, see [Access Control Mechanism in Cross-Device Synchronization](sync-app-data-across-devices-overview.md#access-control-mechanism-in-cross-device-synchronization).
1. Import the module.
```js
import distributedKVStore from '@ohos.data.distributedKVStore';
```
......@@ -115,7 +115,7 @@ The following uses a single KV store as an example to describe how to implement
1. Create a **kvManagerConfig** object based on the application context.
2. Create a **KvManager** instance.
```js
// Obtain the context of the stage model.
import UIAbility from '@ohos.app.ability.UIAbility';
......@@ -152,7 +152,7 @@ The following uses a single KV store as an example to describe how to implement
1. Declare the ID of the distributed KV store to create.
2. Disable the auto synchronization function (**autoSync:false**) to facilitate subsequent verification of the synchronization function. If synchronization is required, call the **sync()** interface.
```js
try {
const options = {
......@@ -179,7 +179,7 @@ The following uses a single KV store as an example to describe how to implement
```
5. Subscribe to changes of distributed data.
```js
try {
kvStore.on('dataChange', distributedKVStore.SubscribeType.SUBSCRIBE_TYPE_ALL, (data) => {
......@@ -195,7 +195,7 @@ The following uses a single KV store as an example to describe how to implement
1. Construct the key and value to be written to the single KV store.
2. Write KV pairs to the single KV store.
```js
const KEY_TEST_STRING_ELEMENT = 'key_test_string';
const VALUE_TEST_STRING_ELEMENT = 'value_test_string';
......@@ -217,7 +217,7 @@ The following uses a single KV store as an example to describe how to implement
1. Construct the key to be queried from the single KV store.
2. Query data from the single KV store.
```js
const KEY_TEST_STRING_ELEMENT = 'key_test_string';
const VALUE_TEST_STRING_ELEMENT = 'value_test_string';
......@@ -249,7 +249,7 @@ The following uses a single KV store as an example to describe how to implement
>
> If manual synchronization is used, **deviceIds** is obtained by using [devManager.getTrustedDeviceListSync](../reference/apis/js-apis-device-manager.md#gettrusteddevicelistsync). The APIs of the **deviceManager** module are all system interfaces and available only to system applications.
```js
import deviceManager from '@ohos.distributedHardware.deviceManager';
......
en/application-dev/database/share-data-by-datashareextensionability.md
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......@@ -16,8 +16,8 @@ There are two roles in **DataShare**:
- Data consumer: accesses the data provided by the provider using [createDataShareHelper()](../reference/apis/js-apis-data-dataShare.md#datasharecreatedatasharehelper).
**Figure 1** Data sharing mechanism
**Figure 1** Data sharing mechanism
![dataShare](figures/dataShare.jpg)
- The **DataShareExtensionAbility** module, as the data provider, implements services related to data sharing between applications.
......@@ -60,7 +60,7 @@ Before implementing a **DataShare** service, you need to create a **DataShareExt
3. Import **@ohos.application.DataShareExtensionAbility** and other dependencies to the **DataShareExtAbility.ts** file, and
override the service implementation as required. For example, if the data provider provides only the data insertion, deletion, and query services, you can override only these APIs.
```js
import Extension from '@ohos.application.DataShareExtensionAbility';
import rdb from '@ohos.data.relationalStore';
......@@ -68,7 +68,7 @@ override the service implementation as required. For example, if the data provid
```
4. Implement the data provider services. For example, implement data storage of the data provider by using a database, reading and writing files, or accessing the network.
```js
const DB_NAME = 'DB00.db';
const TBL_NAME = 'TBL00';
......@@ -126,18 +126,18 @@ override the service implementation as required. For example, if the data provid
**Table 1** Fields in module.json5
| Field| Description| Mandatory|
| Field| Description| Mandatory|
| -------- | -------- | -------- |
| name | Ability name, corresponding to the **ExtensionAbility** class name derived from **Ability**.| Yes|
| type | Ability type. The value is **dataShare**, indicating the development is based on the **datashare** template.| Yes|
| uri | URI used for communication. It is the unique identifier for the data consumer to connect to the provider.| Yes|
| exported | Whether it is visible to other applications. Data sharing is allowed only when the value is **true**.| Yes|
| readPermission | Permission required for accessing data. If this parameter is not set, the read permission is not verified by default.| No|
| writePermission | Permission required for modifying data. If this parameter is not set, write permission verification is not performed by default.| No|
| name | Ability name, corresponding to the **ExtensionAbility** class name derived from **Ability**.| Yes|
| type | Ability type. The value is **dataShare**, indicating the development is based on the **datashare** template.| Yes|
| uri | URI used for communication. It is the unique identifier for the data consumer to connect to the provider.| Yes|
| exported | Whether it is visible to other applications. Data sharing is allowed only when the value is **true**.| Yes|
| readPermission | Permission required for accessing data. If this parameter is not set, the read permission is not verified by default.| No|
| writePermission | Permission required for modifying data. If this parameter is not set, write permission verification is not performed by default.| No|
**module.json5 example**
```json
"extensionAbilities": [
{
......@@ -156,7 +156,7 @@ override the service implementation as required. For example, if the data provid
### Data Consumer Application Development
1. Import the dependencies.
```js
import UIAbility from '@ohos.app.ability.UIAbility';
import dataShare from '@ohos.data.dataShare';
......@@ -164,14 +164,14 @@ override the service implementation as required. For example, if the data provid
```
2. Define the URI string for communicating with the data provider.
```js
// Different from the URI defined in the module.json5 file, the URI passed in the parameter has an extra slash (/), because there is a DeviceID parameter between the second and the third slash (/).
let dseUri = ('datashare:///com.samples.datasharetest.DataShare');
```
3. Create a **DataShareHelper** instance.
```js
let dsHelper;
let abilityContext;
......@@ -187,7 +187,7 @@ override the service implementation as required. For example, if the data provid
```
4. Use the APIs provided by **DataShareHelper** to access the services provided by the provider, for example, adding, deleting, modifying, and querying data.
```js
// Construct a piece of data.
let valuesBucket = { 'name': 'ZhangSan', 'age': 21, 'isStudent': false, 'Binary': new Uint8Array([1, 2, 3]) };
......
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