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创建DataAbility

实现DataAbility中Insert、Query、Update、Delete接口的业务内容。保证能够满足数据库存储业务的基本需求。BatchInsert与ExecuteBatch接口已经在系统中实现遍历逻辑，依赖Insert、Query、Update、Delete接口逻辑，来实现数据的批量处理。

创建DataAbility的代码示例如下：

import featureAbility from '@ohos.ability.featureAbility';
import type common from '@ohos.app.ability.common';
import type Want from '@ohos.app.ability.Want';
import type { AsyncCallback, BusinessError } from '@ohos.base';
import dataAbility from '@ohos.data.dataAbility';
import rdb from '@ohos.data.rdb';
import hilog from '@ohos.hilog';let TABLE_NAME = 'book';
let STORE_CONFIG: rdb.StoreConfig = { name: 'book.db' };
let SQL_CREATE_TABLE = 'CREATE TABLE IF NOT EXISTS book(id INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT NOT NULL, introduction TEXT NOT NULL)';
let rdbStore: rdb.RdbStore | undefined = undefined;
const TAG: string = '[Sample_FAModelAbilityDevelop]';
const domain: number = 0xFF00;class DataAbility {onInitialized(want: Want): void {hilog.info(domain, TAG, 'DataAbility onInitialized, abilityInfo:' + want.bundleName);let context: common.BaseContext = { stageMode: featureAbility.getContext().stageMode };rdb.getRdbStore(context, STORE_CONFIG, 1, (err, store) => {hilog.info(domain, TAG, 'DataAbility getRdbStore callback');store.executeSql(SQL_CREATE_TABLE, []);rdbStore = store;});}insert(uri: string, valueBucket: rdb.ValuesBucket, callback: AsyncCallback<number>): void {hilog.info(domain, TAG, 'DataAbility insert start');if (rdbStore) {rdbStore.insert(TABLE_NAME, valueBucket, callback);}}batchInsert(uri: string, valueBuckets: Array<rdb.ValuesBucket>, callback: AsyncCallback<number>): void {hilog.info(domain, TAG, 'DataAbility batch insert start');if (rdbStore) {for (let i = 0; i < valueBuckets.length; i++) {hilog.info(domain, TAG, 'DataAbility batch insert i=' + i);if (i < valueBuckets.length - 1) {rdbStore.insert(TABLE_NAME, valueBuckets[i], (err: BusinessError, num: number) => {hilog.info(domain, TAG, 'DataAbility batch insert ret=' + num);});} else {rdbStore.insert(TABLE_NAME, valueBuckets[i], callback);}}}}query(uri: string, columns: Array<string>, predicates: dataAbility.DataAbilityPredicates, callback: AsyncCallback<rdb.ResultSet>): void {hilog.info(domain, TAG, 'DataAbility query start');let rdbPredicates = dataAbility.createRdbPredicates(TABLE_NAME, predicates);if (rdbStore) {rdbStore.query(rdbPredicates, columns, callback);}}update(uri: string, valueBucket: rdb.ValuesBucket, predicates: dataAbility.DataAbilityPredicates, callback: AsyncCallback<number>): void {hilog.info(domain, TAG, 'DataAbility update start');let rdbPredicates = dataAbility.createRdbPredicates(TABLE_NAME, predicates);if (rdbStore) {rdbStore.update(valueBucket, rdbPredicates, callback);}}delete(uri: string, predicates: dataAbility.DataAbilityPredicates, callback: AsyncCallback<number>): void {hilog.info(domain, TAG, 'DataAbility delete start');let rdbPredicates = dataAbility.createRdbPredicates(TABLE_NAME, predicates);if (rdbStore) {rdbStore.delete(rdbPredicates, callback);}}
}export default new DataAbility();