删除A表的a列等于1的数据
代码如下 |
复制代码 |
Delete from A where exists (Select 1 from A where a=1)
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上面的方法只适用于简单小数据量的批量数据删除了,如果是大批量数据删除我们可参考下面方法
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 < LEN(@DelCharIndexID))
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
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