Question

我试图通过加入payid来更新payc表的eid来支付表格。在PayC表中，匹配的payid s有重复的eid s'，每个匹配的PAYID只需要一个EID

update PAY
SET eid = (select t.EID from (select a.EID,a.PAYID, count(a.EID) as cnt 
                                                       from PAYC a,PAYC b
                                                            where a.payid = b.payid
                                                            group by a.PAYID,a.eid
                                                            having count( a.eid) > 1) t
                                                            where  T.payid = PAYID)
WHERE EXISTS (select 'X' from (select a.EID,a.PAYID, count(a.EID) as cnt 
                                                       from PAYC a,PAYC b
                                                            where a.payid = b.payid
                                                            group by a.PAYID,a.eid
                                                            having count( a.eid) > 1) t
                                                            where  T.payid = PAYID)

错误：子查询返回的值超过1。当子查询遵循=，！=，＆lt;，＆lt; =，＆gt;，＆gt; =或子查询用作表达式时，不允许这样做。

我们可以通过此查询找到重复的EID，但只需要一个EID

select a.EID,COUNT(a.PAYID), count(a.EID) as cnt 
 from PAYC a,PAYC b
 where a.payid = b.payid
 group by a.PAYID,a.eid
 having count( a.eid) > 1 AND 
 COUNT(a.PAYID) >1

示例数据

paycid payid  eid  amount year  quarter
1       101  1000   2000  2001   1
2       101  1000   3000  2001   2

需要提取

eid
1000

匹配的payid

Answer 1

select top 1 * from stuff

可能会这样做。

Answer 2

这样的事可能会有所帮助吗？

WITH Duplicates AS (
    SELECT
        a.EID,
        a.PAYID,
        ROW_NUMBER() OVER (PARTITION BY a.PAYID ORDER BY a.EID) AS ROWID
    FROM
        PAYC a
        INNER JOIN PAYC b ON b.PAYID = a.PAYID
    GROUP BY
        a.EID,
        a.PAYID
    HAVING
        COUNT(a.EID) > 1)       
UPDATE
    p
SET
    EID = d.EID
FROM
    PAY p
    INNER JOIN Duplicates d ON d.PAYID = p.PAYID AND d.ROWID = 1;

虽然我不得不承认我不理解你从PAYC到PAYC的自我加入的逻辑。当然，您不需要这样做才能找到每个PAYID有多个EID的情况？在这种情况下，您可以完全删除INNER JOIN PAYC b线？

在考虑了这个之后，你能不能简单地做到这一点？

WITH Duplicates AS (
    SELECT
        PAYID,
        MAX(EID) AS EID
    FROM
        PAYC
    GROUP BY
        PAYID
    HAVING
        COUNT(DISTINCT EID) > 1)        
UPDATE
    p
SET
    EID = d.EID
FROM
    PAY p
    INNER JOIN Duplicates d ON d.PAYID = p.PAYID;

然后使用MAX，MIN或您需要的任何聚合来选择您要用来更新PAY表的EID（我的示例使用MAX）。这就是为什么您的原始查询无效，您没有告诉它使用哪个EID，并且它返回了多个值。

使用子查询更新列

2 个答案: