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  • 事务

    ---事务:保障整个流程的完整执行,全部没有问题,统一提交,一旦有问题,回到原点。
    
    begin tran --事务的开始
    --开始写流程语句
    --语句写完之后
    if @@ERROR>0
    begin
    rollback tran--回滚事务
    end
    else
    commit tran --提交事务
    
    
    
    
    --级联删除套入事务中
    alter trigger score_delete
    on score
    instead of delete
    as
        declare @count int
        select @count=count(*)from deleted
        
        declare @i int
        set @i=0
        while @i<@count --循环遍历delete临时表的数据,然后转移到备份表中
        begin
        declare @sno varchar(20)
        declare @cno varchar(20)
        declare @degree decimal(4,1)
        select top 1 @sno=sno,@cno=cno,@degree=degree from deleted where 
        sno not in (select top (@i) sno from deleted)
        or cno not in(select top (@i) cno from deleted)
        
        --下面开始事务
        begin tran
        insert into scorebak values(@sno,@cno,@degree,getdate())
        delete from score where sno =@sno and @cno=@cno
        if @@error>0
        begin
        rollback tran
        end
        else
        commit tran
        
        
        set @i=@i+1
        end
    go
    
    delete from score where Sno=109
    select*from scorebak
    drop table scorebak
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  • 原文地址:https://www.cnblogs.com/lk-kk/p/4467675.html
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