Question

我正在尝试在SQL中为此查询添加一个列，如下所示 -

SELECT DISTINCT
    h.tradingitemid
    ,h.securityid
    ,h.currencyId
    ,CUSIP =
         (
             SELECT gs.holdingsymbol
             FROM CPR.dbo.holdingsymbol_tbl gs
             WHERE gs.holdingsymboltypeid = 2
         )
FROM cpr..holding_tbl             h
INNER JOIN cpr..HoldingSymbol_tbl hs ON h.holdingid = hs.holdingId
WHERE h.userCompanyId = 10;

但问题是这个子查询返回的结果超过1，所以这段代码返回错误。这里是否可以有一个列可以容纳子查询的所有结果？

谢谢，哈

Answer 1

您可以尝试这样做：

CUSIP=(Select TOP 1 gs.holdingsymbol 
           from dbo.holdingsymbol_tbl gs where gs.holdingsymboltypeid=2)

Answer 2

您可以使用xml将查询的所有结果存储到列

CUSIP=(Select gs.holdingsymbol 
           from dbo.holdingsymbol_tbl gs where gs.holdingsymboltypeid=2 for xml path(''))

Answer 3

您不需要子查询，只需要JOIN上的其他条件，就像这样：

SELECT DISTINCT
    h.tradingitemid
    ,h.securityid
    ,h.currencyId
    ,CUSIP = hs.holdingsymbol
FROM cpr..holding_tbl h
INNER JOIN cpr..HoldingSymbol_tbl hs ON h.holdingid = hs.holdingId AND hs.holdingsymboltypeid = 2
WHERE h.userCompanyId = 10;

将列添加到SQL表

3 个答案: