原文:
sql server 带有OUTPUT的INSERT,DELETE,UPDATE
OUTPUT是SQL SERVER2005的新特性.可以从数据修改语句中返回输出.可以看作是"返回结果的DML".INSERT,DELETE,UPDATE均支持OUTPUT子句.在OUTPUT子句中,可以引用特殊表inserted和deleted.使用inserted和deleted表与在触发器中使用的非常相似.
在INSERT,DELETE,UPDATE中OUTPUT的区别
1.对于INSERT,可以引用inserted表以查询新行的属性.
2.对于DELETE,可以引用deleted表以查询旧行的属性.
3.对于UPDATE,使用deleted表查询被更新行在更改前的属性,用inserted表标识被更新行在更改后的值.
输出方式:
1.可以输出给调用方(客户端应用程序)
2.输出给表
3.两者皆可.
应用:
一.带有OUTPUT的INSERT的应用
对于包含自增列的表执行多行insert语句,同时想知道新的标识值时,在INSERT中使用OUTPUT子句非常方便.对于单行INSERT语句,这不成问题:SCOPE_IDENTITY函数即可实现.
- -- Generating Surrogate Keys for Customers
- USE tempdb;
- GO
- IF OBJECT_ID('dbo.CustomersDim') IS NOT NULL
- DROP TABLE dbo.CustomersDim;
- GO
- CREATE TABLE dbo.CustomersDim
- (
- KeyCol INT NOT NULL IDENTITY PRIMARY KEY,
- CustomerID NCHAR(5) NOT NULL,
- CompanyName NVARCHAR(40) NOT NULL,
- /* ... other columns ... */
- );
- -- Insert New Customers and Get their Surrogate Keys
- DECLARE @NewCusts TABLE
- (
- CustomerID NCHAR(5) NOT NULL PRIMARY KEY,
- KeyCol INT NOT NULL UNIQUE
- );
- INSERT INTO dbo.CustomersDim(CustomerID, CompanyName)
- OUTPUT inserted.CustomerID, inserted.KeyCol
- INTO @NewCusts
- -- OUTPUT inserted.CustomerID, inserted.KeyCol
- SELECT CustomerID, CompanyName
- FROM Northwind.dbo.Customers
- WHERE Country = N'UK';
- SELECT CustomerID, KeyCol FROM @NewCusts;
- GO
注意代码中被注释掉的第二个OUTPUT子句,后面没有INTO子句.如果还要输出返回给调用方,取消注释即可.这样,INSERT语句将包含两个OUTPUT子句.
示例2.
- USE AdventureWorks;
- GO
- CREATE TABLE TestTable (ID INT, TEXTVal VARCHAR(100))
-
- DECLARE @TmpTable TABLE (ID INT, TEXTVal VARCHAR(100))
- INSERT TestTable (ID, TEXTVal)
- OUTPUT Inserted.ID, Inserted.TEXTVal INTO @TmpTable
- VALUES (1,'FirstVal')
- INSERT TestTable (ID, TEXTVal)
- OUTPUT Inserted.ID, Inserted.TEXTVal INTO @TmpTable
- VALUES (2,'SecondVal')
- SELECT * FROM @TmpTable
- SELECT * FROM TestTable
- DROP TABLE TestTable
- GO
- USE AdventureWorks;
- GO
-
- CREATE TABLE TestTable (ID INT, TEXTVal VARCHAR(100))
- INSERT TestTable (ID, TEXTVal)
- OUTPUT Inserted.ID, Inserted.TEXTVal
- VALUES (1,'FirstVal')
- INSERT TestTable (ID, TEXTVal)
- OUTPUT Inserted.ID, Inserted.TEXTVal
- VALUES (2,'SecondVal')
-
- DROP TABLE TestTable
- GO
二.带有OUTPUT的DELETE的应用.
如果要删除数据的同时,还需要记录日志,或者归档数据.在DELETE中使用OUTPUT子句在适合不过了.
- USE AdventureWorks;
- GO
- CREATE TABLE TestTable (ID INT, TEXTVal VARCHAR(100))
-
- DECLARE @TmpTable TABLE (ID INT, TEXTVal VARCHAR(100))
-
- INSERT TestTable (ID, TEXTVal)
- VALUES (1,'FirstVal')
- INSERT TestTable (ID, TEXTVal)
- VALUES (2,'SecondVal')
- DELETE
- FROM TestTable
- OUTPUT Deleted.ID, Deleted.TEXTVal INTO @TmpTable
- WHERE ID IN (1,2)
- SELECT * FROM @TmpTable
- SELECT * FROM TestTable
-
- DROP TABLE TestTable
- GO
三.带有OUTPUT的UPDATE的应用
- USE AdventureWorks;
- GO
- CREATE TABLE TestTable (ID INT, TEXTVal VARCHAR(100))
-
- DECLARE @TmpTable TABLE (ID_New INT, TEXTVal_New VARCHAR(100),ID_Old INT, TEXTVal_Old VARCHAR(100))
-
- INSERT TestTable (ID, TEXTVal)
- VALUES (1,'FirstVal')
- INSERT TestTable (ID, TEXTVal)
- VALUES (2,'SecondVal')
-
- UPDATE TestTable
- SET TEXTVal = 'NewValue'
- OUTPUT Inserted.ID, Inserted.TEXTVal, Deleted.ID, Deleted.TEXTVal INTO @TmpTable
- WHERE ID IN (1,2)
- SELECT * FROM @TmpTable
- SELECT * FROM TestTable
-
- DROP TABLE TestTable
- GO
