SQL Server游标和分组依据

Question

我需要将游标与Group by语句结合使用，该语句基于表中的组号:当前代码为我提供了每条记录，假设分别为group 1，这是我不想要的，我希望按分组检索数据。

DECLARE hello CURSOR
    FOR 

SELECT bygpno, SUM(bycash)
    FROM sheet1 
    GROUP BY bygpno
    ORDER BY bygpno


OPEN hello
FETCH NEXT FROM hello

WHILE @@FETCH_STATUS = 0
BEGIN

FETCH NEXT FROM hello

END
    CLOSE hello
    DEALLOCATE hello

当我运行上面的代码时，它在结果中一次检索一行，我不知道为什么。

Answer 1

看起来您需要一个嵌套的游标，因此外部游标会遍历每个组的bygpno值，然后在循环中，您会有另一个游标循环来遍历各个记录

它看起来有点像这样

FETCH NEXT FROM hello INTO @bygpno, @Sum_bycash

WHILE @@FETCH_STATUS = 0
BEGIN

    DECLARE CURSOR helloagain FOR SELECT ...,bycash FROM sheet1 WHERE bygpno = @bygpno
    OPEN CURSOR helloagain 
    FETCH NEXT FROM helloagain INTO ...,@bycash 
    WHILE @@FETCH_STATUS = 0
        BEGIN
        FETCH NEXT FROM helloagain INTO ...,@bycash 
        END
    CLOSE CURSOR helloagain 
    DEALLOCATE CURSOR helloagain 


    FETCH NEXT FROM hello INTO @bygpno, @Sum_bycash
END