数据库事务

批量操作需要使用事务以节省时间

同一类型的数据库操作, 每一次操作都去打开关闭数据库会比较耗时, 此时使用事务的方式去操作数据库, 会将操作暂时缓存起来, 在最后执行时只需要打开一次数据库, 会大大的减少操作时间

新建一个列表存操作

ArrayList<ContentProviderOperation> operations = new ArrayList<ContentProviderOperation>();

1	ArrayList<ContentProviderOperation> operations = new ArrayList<ContentProviderOperation>();

存入操作

一个 ContentProviderOperation 代表一个插入操作

ContentProviderOperation 的方法

静态方法:(返回ContentProviderOperation.Builder对象)

newDelete(Uri uri)
newInsert(Uri uri)
newUpdate(Uri uri)
newAssertQuery(Uri uri)

ContentProviderOperation.Builder 的方法

withSelection(String selection, String[] selectionArgs)
withValueBackReference(String key, int previousResult)

批量操作列表中第 previousResult 个操作的返回值作为该 key 的值 (适用 insert, update, or assert)
withValue(String key, Object value)

A value to insert or update
withYieldAllowed(boolean yieldAllowed)

是否允许其它事务同时操作数据库
build() 末尾调用返回 ContentProviderOperation 对象, 存入列表

执行操作

getContentResolver().applyBatch(String authority, ArrayList operations)

第一个参数实现事务的Provider的authority属性


    public static void addContactToSQL(String name,
            List<Map<String, String>> list, String id) throws Exception
    {
        ArrayList<ContentProviderOperation> operations = new ArrayList<ContentProviderOperation>();

        ContentProviderOperation operation = ContentProviderOperation
                .newInsert(ContactsContract.RawContacts.CONTENT_URI)
                .withValue(ContactsContract.RawContacts.ACCOUNT_TYPE, null)
                .withValue(ContactsContract.RawContacts.ACCOUNT_NAME, null)
                .build();
        operations.add(operation);

        // 添加联系人名称操作
        operation = ContentProviderOperation
                .newInsert(ContactsContract.Data.CONTENT_URI)
                .withValueBackReference(ContactsContract.Data.RAW_CONTACT_ID, 0)
                .withValue(
                        ContactsContract.Data.MIMETYPE,
                        ContactsContract.CommonDataKinds.StructuredName.CONTENT_ITEM_TYPE)
                .withValue(
                        ContactsContract.CommonDataKinds.StructuredName.DISPLAY_NAME,
                        name).build();
        operations.add(operation);

        int size2 = list.size();
        for (int x = 0; x < size2; x++)
        {
            // 向联系人电话号码URI添加电话号码
            operation = ContentProviderOperation
                    .newInsert(ContactsContract.Data.CONTENT_URI)
                    .withValueBackReference(
                            ContactsContract.Data.RAW_CONTACT_ID, 0)
                    .withValue(
                            ContactsContract.Data.MIMETYPE,
                            ContactsContract.CommonDataKinds.Phone.CONTENT_ITEM_TYPE)
                    .withValue(
                            ContactsContract.CommonDataKinds.Phone.TYPE,
                            getClassString(list.get(size2 - 1 - x).get("num")
                                    .substring(0, 1)))
                    .withValue(ContactsContract.CommonDataKinds.Phone.NUMBER,
                            list.get(size2 - 1 - x).get("num").substring(1))
                    .build();
            operations.add(operation);

        }

        ContentResolver resolver = BtApp.getmContext().getContentResolver();
        // 批量执行,返回执行结果集
        ContentProviderResult[] results = resolver.applyBatch(
                ContactsContract.AUTHORITY, operations);
    }

public static void addContactToSQL(String name,

List<Map<String, String>> list, String id) throws Exception

{

ArrayList<ContentProviderOperation> operations = new ArrayList<ContentProviderOperation>();

ContentProviderOperation operation = ContentProviderOperation

.newInsert(ContactsContract.RawContacts.CONTENT_URI)

.withValue(ContactsContract.RawContacts.ACCOUNT_TYPE, null)

.withValue(ContactsContract.RawContacts.ACCOUNT_NAME, null)

.build();

operations.add(operation);

// 添加联系人名称操作

operation = ContentProviderOperation

.newInsert(ContactsContract.Data.CONTENT_URI)

.withValueBackReference(ContactsContract.Data.RAW_CONTACT_ID, 0)

.withValue(

ContactsContract.Data.MIMETYPE,

ContactsContract.CommonDataKinds.StructuredName.CONTENT_ITEM_TYPE)

.withValue(

ContactsContract.CommonDataKinds.StructuredName.DISPLAY_NAME,

name).build();

operations.add(operation);

int size2 = list.size();

for (int x = 0; x < size2; x++)

{

// 向联系人电话号码URI添加电话号码

operation = ContentProviderOperation

.newInsert(ContactsContract.Data.CONTENT_URI)

.withValueBackReference(

ContactsContract.Data.RAW_CONTACT_ID, 0)

.withValue(

ContactsContract.Data.MIMETYPE,

ContactsContract.CommonDataKinds.Phone.CONTENT_ITEM_TYPE)

.withValue(

ContactsContract.CommonDataKinds.Phone.TYPE,

getClassString(list.get(size2 - 1 - x).get("num")

.substring(0, 1)))

.withValue(ContactsContract.CommonDataKinds.Phone.NUMBER,

list.get(size2 - 1 - x).get("num").substring(1))

.build();

operations.add(operation);

}

ContentResolver resolver = BtApp.getmContext().getContentResolver();

// 批量执行,返回执行结果集

ContentProviderResult[] results = resolver.applyBatch(

ContactsContract.AUTHORITY, operations);

}

第二种方法(只记录, 未验证)

SQLiteDatabase db ... ;

//开启事务  
db.beginTransaction()
....
//数据库操作
....
//设置事务标志为成功，当结束事务时就会提交事务  
db.setTransactionSuccessful();
//结束事务, 执行数据库操作
db.endTransaction();

SQLiteDatabase db ... ;

//开启事务

db.beginTransaction()

....

//数据库操作

....

//设置事务标志为成功，当结束事务时就会提交事务

db.setTransactionSuccessful();

//结束事务, 执行数据库操作

db.endTransaction();

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