Question

我有两个单独的选择语句。它们都选择了PrimaryID，但它们也选择了未共享的列，例如PrimaryID。我正在使用内部联接来获得我的结果，如下所示：

PrimaryID | col2 | col3 | PrimaryID | col4 | col5
    1         2      3        1         2      3
    1         3      4        1         3      4
    1         5      6        1         5      6
    2         3      4        2         3      4
    2         5      6        2         5      6
    2         7      8        2         7      8

想要的是：

PrimaryID | col2 | col3 | PrimaryID | col4 | col5
    1         2      3        1         2      3
                              1         3      4
                              1         5      6
    2         3      4        2         3      4
                              2         5      6
                              2         7      8

无论如何我能做到这一点吗？感谢。

QUERY：

Select * from
    (SELECT primaryid, col2, col3
    from g.table
    left join (random stuff)
    WHERE DATEPART(m, CreateDateTime) = DATEPART(m, DATEADD(m, -1, getdate()))
    AND DATEPART(yyyy, CreateDateTime) = DATEPART(yyyy, DATEADD(m, -1, getdate()))) t1
inner join
    (select primaryid, col4, col5
    from g.table
    where primaryid in (select primaryid from g.table) and col5 = 0) t2
    on t1.primaryid = t2.primaryid
    order by t1.col2

Answer 1

您的查询在语法上不正确，所以我的建议也不是，但您会明白：使用ROW_NUMBER和OVER(PARTITION BY ...)来获取编号的子集。然后使用CASE仅在数字为“1”的行中强制所需的值。其他行返回空字符串或NULL。

注意：我将两个名称相同的primaryid列更改为ID1和ID2：

WITH Numbered AS
(
    Select *
          ,ROW_NUMBER() OVER(PARTITION BY ID1 ORDER BY col2,col3) AS SortNumber
    from
        (SELECT primaryid AS ID1, col2, col3
        from g.table
        left join (random stuff)
        WHERE DATEPART(m, CreateDateTime) = DATEPART(m, DATEADD(m, -1, getdate()))
        AND DATEPART(yyyy, CreateDateTime) = DATEPART(yyyy, DATEADD(m, -1, getdate()))) t1
    inner join
        (select primaryid AS ID2, col4, col5
        from g.table
        where primaryid in (select primaryid from g.table) and col5 = 0) t2
        on t1.ID1 = t2.ID2
)
SELECT CASE WHEN SortNumber=1 THEN ID1 ELSE '' END AS ID1
      ,CASE WHEN SortNumber=1 THEN col2 ELSE '' END AS col2
      ,CASE WHEN SortNumber=1 THEN col3 ELSE '' END AS col3
      ,ID2,col4,col5
FROM Numbered

使用相同的列两次，但删除第一列重复

1 个答案: