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提交 e39714aa 编写于 作者: A Annie_wang
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update docs 

Signed-off-by: NAnnie_wang <annie.wangli@huawei.com>
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en/application-dev/database/database-relational-guidelines.md
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......@@ -37,14 +37,14 @@ The RDB provides APIs for inserting, deleting, updating, and querying data in th
- **Updating Data**
Call **update()** to update data based on the passed data and the conditions specified by **RdbPredicates**. If the data is updated, the number of rows of the updated data will be returned; otherwise, **0** will be returned.
Call **update()** to pass the new data and specify the update conditions by using **RdbPredicates**. If the data is updated, the number of rows of the updated data will be returned; otherwise, **0** will be returned.
**Table 3** API for updating data
| Class | API | Description |
| ---------- | ------------------------------------------------------------ | ------------------------------------------------------------ |
| RdbStore | update(values: ValuesBucket, predicates: RdbPredicates): Promise&lt;number&gt; | Updates data based on the specified **RdbPredicates** object. This API uses a promise to return the number of rows updated.<br>- **values**: data to update, which is stored in **ValuesBucket**.<br>- **predicates**: conditions for updating data. |
| RdbStore | update(values: ValuesBucket, predicates: RdbPredicates): Promise&lt;number&gt; | Updates data based on the specified **RdbPredicates** object. This API uses a promise to return the number of rows updated.<br>- **values**: data to update, which is stored in **ValuesBucket**.<br>- **predicates**: conditions for updating data.|
- **Deleting Data**
......@@ -55,7 +55,7 @@ The RDB provides APIs for inserting, deleting, updating, and querying data in th
| Class | API | Description |
| ---------- | ---------------------------------------------------------- | ------------------------------------------------------------ |
| RdbStore | delete(predicates: RdbPredicates): Promise&lt;number&gt; | Deletes data from the RDB store based on the specified **RdbPredicates** object. This API uses a promise to return the number of rows deleted.<br>- **predicates**: conditions for deleting data. |
| RdbStore | delete(predicates: RdbPredicates): Promise&lt;number&gt; | Deletes data from the RDB store based on the specified **RdbPredicates** object. This API uses a promise to return the number of rows deleted.<br>- **predicates**: conditions for deleting data.|
- **Querying Data**
......@@ -201,76 +201,81 @@ You can obtain the distributed table name for a remote device based on the local
FA model:
```js
import data_rdb from '@ohos.data.relationalStore'
import relationalStore from '@ohos.data.relationalStore'
import featureAbility from '@ohos.ability.featureAbility'
var store;
// Obtain the context.
let context = featureAbility.getContext()
let context = featureAbility.getContext();
const STORE_CONFIG = {
name: "RdbTest.db",
securityLevel: data_rdb.SecurityLevel.S1
}
securityLevel: relationalStore.SecurityLevel.S1
};
// Assume that the current RDB store version is 3.
data_rdb.getRdbStore(context, STORE_CONFIG, function (err, rdbStore) {
// When an RDB store is created, the default version is 0.
if (rdbStore.version == 0) {
rdbStore.executeSql("CREATE TABLE IF NOT EXISTS student (id INTEGER PRIMARY KEY AUTOINCREMENT, score REAL);", null)
// Set the RDB store version. The input parameter must be an integer greater than 0.
rdbStore.version = 3
}
relationalStore.getRdbStore(context, STORE_CONFIG, function (err, rdbStore) {
store = rdbStore;
// When an RDB store is created, the default version is 0.
if (store.version == 0) {
store.executeSql("CREATE TABLE IF NOT EXISTS student (id INTEGER PRIMARY KEY AUTOINCREMENT, score REAL);", null);
// Set the RDB store version. The input parameter must be an integer greater than 0.
store.version = 3;
}
// When an app is updated to the current version, the RDB store needs to be updated from version 1 to version 2.
if (rdbStore.version != 3 && rdbStore.version == 1) {
// version = 1: table structure: student (id, age) => version = 2: table structure: student (id, age, score)
rdbStore.executeSql("ALTER TABLE student ADD COLUMN score REAL", null)
rdbStore.version = 2
}
// When an app is updated to the current version, the RDB store needs to be updated from version 1 to version 2.
if (store.version != 3 && store.version == 1) {
// version = 1: table structure: student (id, age) => version = 2: table structure: student (id, age, score)
store.executeSql("ALTER TABLE student ADD COLUMN score REAL", null);
store.version = 2;
}
// When an app is updated to the current version, the RDB store needs to be updated from version 2 to version 3.
if (rdbStore.version != 3 && rdbStore.version == 2) {
// version = 2: table structure: student (id, age, score) => version = 3: table structure: student (id, score)
rdbStore.executeSql("ALTER TABLE student DROP COLUMN age INTEGER", null)
rdbStore.version = 3
}
// When an app is updated to the current version, the RDB store needs to be updated from version 2 to version 3.
if (store.version != 3 && store.version == 2) {
// version = 2: table structure: student (id, age, score) => version = 3: table structure: student (id, score)
store.executeSql("ALTER TABLE student DROP COLUMN age INTEGER", null);
store.version = 3;
}
})
```
Stage model:
```ts
import data_rdb from '@ohos.data.relationalStore'
import relationalStore from '@ohos.data.relationalStore'
import UIAbility from '@ohos.app.ability.UIAbility'
class EntryAbility extends UIAbility {
onWindowStageCreate(windowStage) {
const STORE_CONFIG = {
name: "rdbstore.db",
securityLevel: data_rdb.SecurityLevel.S1
}
var store;
const STORE_CONFIG = {
name: "RdbTest.db",
securityLevel: relationalStore.SecurityLevel.S1
};
// Assume that the current RDB store version is 3.
data_rdb.getRdbStore(this.context, STORE_CONFIG, function (err, rdbStore) {
// When an RDB store is created, the default version is 0.
if (rdbStore.version == 0) {
rdbStore.executeSql("CREATE TABLE IF NOT EXISTS student (id INTEGER PRIMARY KEY AUTOINCREMENT, score REAL);", null)
// Set the RDB store version. The input parameter must be an integer greater than 0.
rdbStore.version = 3
}
// Assume that the current RDB store version is 3.
relationalStore.getRdbStore(this.context, STORE_CONFIG, function (err, rdbStore) {
store = rdbStore;
// When an RDB store is created, the default version is 0.
if (store.version == 0) {
store.executeSql("CREATE TABLE IF NOT EXISTS student (id INTEGER PRIMARY KEY AUTOINCREMENT, score REAL);", null);
// Set the RDB store version. The input parameter must be an integer greater than 0.
store.version = 3;
}
// When an app is updated to the current version, the RDB store needs to be updated from version 1 to version 2.
if (rdbStore.version != 3 && rdbStore.version == 1) {
// version = 1: table structure: student (id, age) => version = 2: table structure: student (id, age, score)
rdbStore.executeSql("ALTER TABLE student ADD COLUMN score REAL", null)
rdbStore.version = 2
}
// When an app is updated to the current version, the RDB store needs to be updated from version 1 to version 2.
if (store.version != 3 && store.version == 1) {
// version = 1: table structure: student (id, age) => version = 2: table structure: student (id, age, score)
store.executeSql("ALTER TABLE student ADD COLUMN score REAL", null);
store.version = 2;
}
// When an app is updated to the current version, the RDB store needs to be updated from version 2 to version 3.
if (rdbStore.version != 3 && rdbStore.version == 2) {
// version = 2: table structure: student (id, age, score) => version = 3: table structure: student (id, score)
rdbStore.executeSql("ALTER TABLE student DROP COLUMN age INTEGER", null)
rdbStore.version = 3
}
})
// When an app is updated to the current version, the RDB store needs to be updated from version 2 to version 3.
if (store.version != 3 && store.version == 2) {
// version = 2: table structure: student (id, age, score) => version = 3: table structure: student (id, score)
store.executeSql("ALTER TABLE student DROP COLUMN age INTEGER", null);
store.version = 3;
}
})
}
}
```
......@@ -284,23 +289,24 @@ You can obtain the distributed table name for a remote device based on the local
The sample code is as follows:
```js
let u8 = new Uint8Array([1, 2, 3])
const valueBucket = { "name": "Tom", "age": 18, "salary": 100.5, "blobType": u8 }
let insertPromise = rdbStore.insert("test", valueBucket)
let u8 = new Uint8Array([1, 2, 3]);
const valueBucket = { "name": "Tom", "age": 18, "salary": 100.5, "blobType": u8 };
let insertPromise = store.insert("test", valueBucket);
```
```js
// Use a transaction to insert data.
beginTransaction()
try {
let u8 = new Uint8Array([1, 2, 3])
const valueBucket1 = { "name": "Tom", "age": 18, "salary": 100.5, "blobType": u8 }
const valueBucket2 = { "name": "Jam", "age": 19, "salary": 200.5, "blobType": u8 }
let insertPromise1 = rdbStore.insert("test", valueBucket1)
let insertPromise2 = rdbStore.insert("test", valueBucket2)
commit()
} catch (e) {
rollBack()
store.beginTransaction();
let u8 = new Uint8Array([1, 2, 3]);
const valueBucket = { "name": "Tom", "age": 18, "salary": 100.5, "blobType": u8 };
let promise = store.insert("test", valueBucket);
promise.then(() => {
store.commit();
})
} catch (err) {
console.error(`Transaction failed, err: ${err}`);
store.rollBack();
}
```
......@@ -315,17 +321,17 @@ You can obtain the distributed table name for a remote device based on the local
The sample code is as follows:
```js
let predicates = new data_rdb.RdbPredicates("test");
predicates.equalTo("name", "Tom")
let promisequery = rdbStore.query(predicates)
let predicates = new relationalStore.RdbPredicates("test");
predicates.equalTo("name", "Tom");
let promisequery = store.query(predicates);
promisequery.then((resultSet) => {
resultSet.goToFirstRow()
const id = resultSet.getLong(resultSet.getColumnIndex("id"))
const name = resultSet.getString(resultSet.getColumnIndex("name"))
const age = resultSet.getLong(resultSet.getColumnIndex("age"))
const salary = resultSet.getDouble(resultSet.getColumnIndex("salary"))
const blobType = resultSet.getBlob(resultSet.getColumnIndex("blobType"))
resultSet.close()
resultSet.goToFirstRow();
const id = resultSet.getLong(resultSet.getColumnIndex("id"));
const name = resultSet.getString(resultSet.getColumnIndex("name"));
const age = resultSet.getLong(resultSet.getColumnIndex("age"));
const salary = resultSet.getDouble(resultSet.getColumnIndex("salary"));
const blobType = resultSet.getBlob(resultSet.getColumnIndex("blobType"));
resultSet.close();
})
```
......@@ -335,9 +341,9 @@ You can obtain the distributed table name for a remote device based on the local
```json
"requestPermissions":
{
"name": "ohos.permission.DISTRIBUTED_DATASYNC"
}
{
"name": "ohos.permission.DISTRIBUTED_DATASYNC"
}
```
(2) Obtain the required permissions.
......@@ -351,13 +357,13 @@ You can obtain the distributed table name for a remote device based on the local
```js
let context = featureAbility.getContext();
context.requestPermissionsFromUser(['ohos.permission.DISTRIBUTED_DATASYNC'], 666, function (result) {
console.info(`result.requestCode=${result.requestCode}`)
console.info(`result.requestCode=${result.requestCode}`);
})
let promise = rdbStore.setDistributedTables(["test"])
let promise = store.setDistributedTables(["test"]);
promise.then(() => {
console.info("setDistributedTables success.")
console.info(`setDistributedTables success.`);
}).catch((err) => {
console.info("setDistributedTables failed.")
console.error(`setDistributedTables failed, ${err}`);
})
```
......@@ -372,16 +378,16 @@ You can obtain the distributed table name for a remote device based on the local
The sample code is as follows:
```js
let predicate = new data_rdb.RdbPredicates('test')
predicate.inDevices(['12345678abcde'])
let promise = rdbStore.sync(data_rdb.SyncMode.SYNC_MODE_PUSH, predicate)
let predicate = new relationalStore.RdbPredicates('test');
predicate.inDevices(['12345678abcde']);
let promise = store.sync(relationalStore.SyncMode.SYNC_MODE_PUSH, predicate);
promise.then((result) => {
console.log('sync done.')
for (let i = 0; i < result.length; i++) {
console.log('device=' + result[i][0] + 'status=' + result[i][1])
}
console.info(`sync done.`);
for (let i = 0; i < result.length; i++) {
console.info(`device=${result[i][0]}, status=${result[i][1]}`);
}
}).catch((err) => {
console.log('sync failed')
console.error(`sync failed, err: ${err}`);
})
```
......@@ -395,15 +401,15 @@ You can obtain the distributed table name for a remote device based on the local
```js
function storeObserver(devices) {
for (let i = 0; i < devices.length; i++) {
console.log('device=' + device[i] + 'data changed')
}
for (let i = 0; i < devices.length; i++) {
console.info(`device= ${devices[i]} data changed`);
}
}
try {
rdbStore.on('dataChange', data_rdb.SubscribeType.SUBSCRIBE_TYPE_REMOTE, storeObserver)
store.on('dataChange', relationalStore.SubscribeType.SUBSCRIBE_TYPE_REMOTE, storeObserver);
} catch (err) {
console.log('register observer failed')
console.error(`register observer failed, err: ${err}`);
}
```
......@@ -416,8 +422,24 @@ You can obtain the distributed table name for a remote device based on the local
The sample code is as follows:
```js
let tableName = rdbStore.obtainDistributedTableName(deviceId, "test");
let resultSet = rdbStore.querySql("SELECT * FROM " + tableName)
import deviceManager from '@ohos.distributedHardware.deviceManager'
let deviceIds = [];
deviceManager.createDeviceManager('bundleName', (err, value) => {
if (!err) {
let devManager = value;
if (devManager != null) {
// Obtain device IDs.
let devices = devManager.getTrustedDeviceListSync();
for (let i = 0; i < devices.length; i++) {
deviceIds[i] = devices[i].deviceId;
}
}
}
})
let tableName = store.obtainDistributedTableName(deviceIds[0], "test");
let resultSet = store.querySql("SELECT * FROM " + tableName);
```
8. Query data of a remote device.
......@@ -429,19 +451,19 @@ You can obtain the distributed table name for a remote device based on the local
The sample code is as follows:
```js
let rdbPredicate = new data_rdb.RdbPredicates('employee')
predicates.greaterThan("id", 0)
let promiseQuery = rdbStore.remoteQuery('12345678abcde', 'employee', rdbPredicate)
let rdbPredicate = new relationalStore.RdbPredicates('employee');
predicates.greaterThan("id", 0) ;
let promiseQuery = store.remoteQuery('12345678abcde', 'employee', rdbPredicate);
promiseQuery.then((resultSet) => {
while (resultSet.goToNextRow()) {
let idx = resultSet.getLong(0);
let name = resultSet.getString(1);
let age = resultSet.getLong(2);
console.info(idx + " " + name + " " + age);
}
resultSet.close();
while (resultSet.goToNextRow()) {
let idx = resultSet.getLong(0);
let name = resultSet.getString(1);
let age = resultSet.getLong(2);
console.info(`indx: ${idx}, name: ${name}, age: ${age}`);
}
resultSet.close();
}).catch((err) => {
console.info("failed to remoteQuery, err: " + err)
console.error(`failed to remoteQuery, err: ${err}`);
})
```
......@@ -452,11 +474,11 @@ You can obtain the distributed table name for a remote device based on the local
The sample code is as follows:
```js
let promiseBackup = rdbStore.backup("dbBackup.db")
let promiseBackup = store.backup("dbBackup.db");
promiseBackup.then(() => {
console.info('Backup success.')
console.info(`Backup success.`);
}).catch((err) => {
console.info('Backup failed, err: ' + err)
console.error(`Backup failed, err: ${err}`);
})
```
......@@ -465,10 +487,10 @@ You can obtain the distributed table name for a remote device based on the local
The sample code is as follows:
```js
let promiseRestore = rdbStore.restore("dbBackup.db")
let promiseRestore = store.restore("dbBackup.db");
promiseRestore.then(() => {
console.info('Restore success.')
console.info(`Restore success.`);
}).catch((err) => {
console.info('Restore failed, err: ' + err)
console.error(`Restore failed, err: ${err}`);
})
```
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