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  • sqlserver 游标写法

    表结构:People表,PeopleDetail表

    1.简单游标

    declare m_cursor cursor scroll for 
    select  Address,PeopleId from  PeopleDetail
    
    open m_cursor
    declare   @Address varchar(50), @PeopleId int
    
    fetch next from m_cursor into @Address,@PeopleId
    while @@FETCH_STATUS=0
    begin
    	print @Address + convert(varchar(3), @PeopleId)
    	fetch next from m_cursor into @Address,@PeopleId
    end
    
    close m_cursor
    deallocate m_cursor
    

    2.用于更新的游标 

    -- 定义游标
    declare m_cursor cursor scroll for 
    select a.Id,b.Address from  People a left join PeopleDetail b on a.Id=b.PeopleId
    for update
    -- 打开游标
    open m_cursor
    declare   @Address varchar(50), @Id int
    --填充数据
    fetch next from m_cursor into @Id,@Address
    --假如检索到了数据,才处理
    while @@FETCH_STATUS=0
    begin
    	update People set  Address=@Address where current of m_cursor
    	--填充下一条数据
    	fetch next from m_cursor into @Id,@Address
    end
    -- 关闭游标
    close m_cursor
    --释放游标
    deallocate m_cursor
    

      

     

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  • 原文地址:https://www.cnblogs.com/kingteach/p/3801054.html
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