1. OUTPUT ... INTO
用于将一条记录从表一移动到表二时非常好用，常见于备份记录的应用
例一：
DELETE [TableUseing]
OUTPUT Deleted.*
INTO [TableBak]
例二：（用于移动时修改某字段的值）
DELETE [TableUseing]
OUTPUT Deleted.Field1, Deleted.Field2, GETDATE()
INTO [TableBak]
2.表变量
用于存储临时的查询结果
DECLARE @tmp TABLE (ID INT, CITY NVARCHAR(50))
INSERT INTO @tmp
SELECT MIN(ID), CITY
FROM [TableTest] WITH(NOCLOCK)
GROUP BY CITY
