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sql批量删除数据与批量删除数据库表语句

Jun 07, 2016 pm 05:49 PM
delete data

我们介绍了二种批量删除数据的方法(游标形式和sql存储过程),同时还介绍了批量删除数据库表的方法,有需要的同学可参考一下。

游标删除方法

 代码如下 复制代码

//定义游标

DECLARE tables_cursor CURSOR

FOR

SELECT name FROM sysobjects WHERE type = 'U' //选择用户表名

OPEN tables_cursor //打开游标连接

 

DECLARE @tablename sysname // 定义变量

FETCH NEXT FROM tables_cursor INTO @tablename //结果集中一行一行读取表名

WHILE (@@FETCH_STATUS -1) //判断游标状态

BEGIN

 

EXEC ('TRUNECATE TABLE ' + @tablename) //清空表中的数据

FETCH NEXT FROM tables_cursor INTO @tablename //下一行数据

END

 

DEALLOCATE tables_cursor //关闭游标

/42850.htm target=_blank >sql存储过程实例地

 代码如下 复制代码

Create PROCEDURE Batch_Delete
@TableName nvarchar(100), --表名
@FieldName nvarchar(100), --删除字段名
@DelCharIndexID nvarchar(1000)
as
DECLARE @PointerPrev int
DECLARE @PointerCurr int
DECLARE @TId NVARCHAR(50), @sql NVARCHAR(1000)

Set @PointerPrev = 1
while (@PointerPrev Begin
Set @PointerCurr = CharIndex(',',@DelCharIndexID,@PointerPrev)
if(@PointerCurr>0)
Begin
SET @TId = cast(SUBSTRING(@DelCharIndexID, @PointerPrev, @PointerCurr - @PointerPrev) As NVARCHAR(50))
SET @sql = 'Delete From '+ @TableName +' Where '+ @FieldName + ' = '''+ @TID+''''
Exec(@Sql)
Print('======='+@TId+'=======sql'+@Sql)
SET @PointerPrev = @PointerCurr + 1
Print(@PointerPrev)
End
else
Begin
Print('break')
Break
End
End
--删除最后一个,因为最后一个后面没有逗号,所以在循环中跳出,需另外再删除
SET @TId = cast(SUBSTRING(@DelCharIndexID, @PointerPrev, LEN(@DelCharIndexID) - @PointerPrev + 1) As NVARCHAR(50))
SET @sql = 'Delete From '+ @TableName +' Where '+ @FieldName + ' = '''+ @TID+''''
Exec(@Sql)
Print('======='+@TId+'=======sql'+@Sql)
GO

网上找的批量删除表方法

 代码如下 复制代码

  /*--------------------------------

功能说明:  批量DropTable

使用说明:  使用时一定要小心,因为删选表的where条件是like所有必须保证where

后的like确定与你要删除表名相匹配

---------------------------------*/

--------参数定义-------------------

DECLARE @tableName AS Nvarchar(50) --查询表名条件(小心!,确保like条件是你要Drop的表.TableName尽量精确)

SET @tableName='test' 

--------------------------------------

--SELECT name FROM sys.tables   WHERE name LIKE '%'+@tableName+'%' --查询出要删除表的名称

IF @tableName='' SET @tableName='tableName'--初始化TableName为tableName,防止@tableName为空

DECLARE @tableNames AS Nvarchar(3000)

DECLARE @sql AS Nvarchar(3000)

SET @tableNames=

(SELECT ','+name FROM sys.tables   WHERE name LIKE '%'+@tableName+'%'  FOR XML PATH(''))

SET @tableNames= Stuff(@tableNames,1,1,'')

SET @sql='DROP TABLE '+@tableNames

EXEC(@sql)

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