Sql 我们可以在一个查询中使用两个pivot吗？

我使用了上面的存储过程，得到了如下输出

Declare @tbl table(SessionId varchar(max),ItemID_FK int,Roles varchar(max))
    insert into @tbl
    select distinct SessionID,ItemID_FK,Roles from tbl_Answers where ID_FK=@ID
    SELECT ItemID_PK,ItemName,case when [Role1] IS NULL then 0 else [Role1] end as [Role1],
    case when [Role2] IS NULL then 0 else [Role2] end as [Role2],
    case when [Role3] IS NULL then 0 else [Role3] end as [Role3],
    case when [Role4] IS NULL then 0 else [Role4] end as [Role4],
    case when [Role5] IS NULL then 0 else [Role5] end as [Role5],
    case when [Role6] IS NULL then 0 else [Role6] end as [Role6],
    case when [Role7] IS NULL then 0 else [Role7] end as [Role7]
    FROM 
    (
    select  items.ItemID_PK ,items.ItemName,count(ans.Roles) as cntRoles,ans.Roles from tbl_Items items Full  join  @tbl ans
    on items.ItemID_PK=ans.ItemID_FK where items.ID_FK= @ID group by Roles,ItemName , items.ItemID_PK
    ) d  PIVOT
     (
          max(cntRoles)
          FOR Roles IN ([Role1],[Role2],[Role3],[Role4],[Role5],[Role6],[Role7])
     ) AS pvt order by ItemID_PK

我有另一个查询，得到了以下输出

+----------+----------+-----+-----+-----+-----+-----+-----+-----+
|ItemID_PK |ItemName  |Role1|Role2|Role3|Role4|Role5|Role6|Role7|
+----------+----------+-----+-----+-----+-----+-----+-----+-----+
|  111     | aaaaa    | 6   |  5  | 0   | 5   |   1 |  4  |  2  |
|  222     | bbbbb    | 1   |  1  | 7   | 2   |   0 |  3  |  1  |
+----------+----------+-----+-----+-----+-----+-----+-----+-----+

我需要合并以上两个输出以生成如下结果

Select Category,Answer,Roles
from tbl_Answers where ID_FK=1 and Category='OtherText'

+---------+--------+-----+
|Category |Answer  |Roles|
+---------+--------+-----+
|OtherText| xxx    |Role1|
|OtherText| yyy    |Role1|
|OtherText| zzz    |Role2|
|OtherText| xzx    |Role3|
+---------+--------+-----+

如何将第二个查询与第一个pivot查询组合以获得上述结果

---

提前感谢。

使用UNION组合两个枢轴。

您可以使用

UNION ALL

组合两个结果，您需要将顶部查询中的角色从int转换为VARCHAR，不过：

+----------+----------+-----+-----+-----+-----+-----+-----+-----+
|ItemID_PK |ItemName  |Role1|Role2|Role3|Role4|Role5|Role6|Role7|
+----------+----------+-----+-----+-----+-----+-----+-----+-----+
|  111     | aaaaa    | 6   |  5  | 0   | 5   |   1 |  4  |  2  |
|  222     | bbbbb    | 1   |  1  | 7   | 2   |   0 |  3  |  1  |
|  Null    | Othertext| xxx | zzz | xzx | saa |     | xxx |     |
|  Null    | Othertext| yyy |     |     | zxz |     |     |     |
+----------+----------+-----+-----+-----+-----+-----+-----+-----+

注意，我已更改此表达式：

DECLARE @ID INT = 1;

WITH Ans AS
(   SELECT  DISTINCT SessionID,ItemID_FK,Roles 
    FROM    tbl_Answers 
    WHERE   ID_FK = @ID
), PivotData AS
(   SELECT  items.ItemID_PK,
            items.ItemName,
            cntRoles = COUNT(ans.Roles),
            ans.Roles 
    FROM    tbl_Items items 
            FULL JOIN Ans
                ON items.ItemID_PK = ans.ItemID_FK 
    WHERE   items.ID_FK = @ID 
    GROUP BY Roles,ItemName, items.ItemID_PK

)
SELECT  ItemID_PK,
        ItemName,
        [Role1] = CAST(ISNULL([Role1], 0) AS VARCHAR(255)),
        [Role2] = CAST(ISNULL([Role2], 0) AS VARCHAR(255)),
        [Role3] = CAST(ISNULL([Role3], 0) AS VARCHAR(255)),
        [Role4] = CAST(ISNULL([Role4], 0) AS VARCHAR(255)),
        [Role5] = CAST(ISNULL([Role5], 0) AS VARCHAR(255)),
        [Role6] = CAST(ISNULL([Role6], 0) AS VARCHAR(255)),
        [Role7] = CAST(ISNULL([Role7], 0) AS VARCHAR(255))
FROM    PivotData
        PIVOT
        (   MAX(cntRoles)
            FOR Roles IN ([Role1],[Role2],[Role3],[Role4],[Role5],[Role6],[Role7])
        ) AS pvt 
UNION ALL
SELECT  ItemID_PK = NULL,
        ItemName = Category,
        [Role1] = ISNULL([Role1], ''),
        [Role2] = ISNULL([Role2], ''),
        [Role3] = ISNULL([Role3], ''),
        [Role4] = ISNULL([Role4], ''),
        [Role5] = ISNULL([Role5], ''),
        [Role6] = ISNULL([Role6], ''),
        [Role7] = ISNULL([Role7], '')
FROM    (   SELECT  Category,Answer,Roles
            FROM    tbl_Answers 
            WHERE   ID_FK = 1 
            AND     Category = 'OtherText'
        ) pd
        PIVOT
        (   MAX(Answer)
            FOR Roles IN ([Role1],[Role2],[Role3],[Role4],[Role5],[Role6],[Role7])
        ) AS pvt 
ORDER BY ItemID_PK;

到

---

因为效果是一样的，但是要短得多。我还删除了表变量，只是将相同的查询放在一个公共表表达式中，因为填充一个表变量然后只引用它一次似乎是多余的。您正在删除对实际表的索引和统计信息的使用，但没有获得任何好处。

谢谢您的回复。它很好用。我不喜欢普通的餐桌用语。谢谢你。你能详细说明一下吗？现在你的答案看起来更像是一个评论。

case when [Role2] IS NULL then 0 else [Role2] end

ISNULL([Role2], 0)