Sql 如何将两列转置到行
我目前将此表用于调查,在调查中,我只需要对第3个问题的回答和评论,而只需要对第4个问题的评论Sql 如何将两列转置到行,sql,sql-server,Sql,Sql Server,我目前将此表用于调查,在调查中,我只需要对第3个问题的回答和评论,而只需要对第4个问题的评论 +---------------------------------------------------+ | Employee | SurveyNo | Question | Answer | Comment | +----------+----------+----------+--------+---------+ | 100 | 1 | 1 |Neutral
+---------------------------------------------------+
| Employee | SurveyNo | Question | Answer | Comment |
+----------+----------+----------+--------+---------+
| 100 | 1 | 1 |Neutral | NULL |
| 100 | 1 | 2 | Hard | NULL |
| 100 | 1 | 3 | Easy | asdfs |
| 100 | 1 | 4 | NULL | ssafa |
| 200 | 2 | 1 | Hard | NULL |
| 200 | 2 | 2 | Hard | NULL |
| 200 | 2 | 3 | Easy | asdfs |
| 200 | 2 | 4 | NULL | NULL |
+---------------------------------------------------+
我要找的是这样的东西
+--------------------------------------------------------------------------------+
| Employee | surveyNo |Question1 | Question2 | Question3 | CommentsQ3 | Comments |
+----------+----------+----------+-----------+-----------+------------+----------+
| 100 | 1 | Neutral | Hard | Easy | asdfs | ssafa |
| 200 | 2 | Hard | Hard | Easy | asdfs | |
+--------------------------------------------------------------------------------+
目前我可以得到每一个问题,但不是评论,我只想得到第三个问题的评论和第四个问题的评论
但是当我包含注释时,我开始得到重复的行
SELECT Employee,surveyNo,[1] as Question1,[2] as Question2,[3] as Question3
FROM
(
SELECT Employee,surveyNo,answer FROM Surveys WHERE Question in (1,2,3)
) d
pivot
(
max(answer)
for Question in ([1],[2],[3])
) piv
您可以执行条件聚合:
SELECT Employee, surveyNo,
MAX(CASE WHEN Question = 1 THEN Answer END) AS Question1 ,
. . .
MAX(CASE WHEN Question = 1 THEN Comment END) AS CommentsQ1,
. . .
FROM Surveys
WHERE Question in (1,2,3)
GROUP BY Employee, surveyNo;
谢谢我想我把自己搞得太复杂了。它的表现也非常快。
SELECT Employee, surveyNo,
MAX(CASE WHEN Question = 1 THEN Answer END) AS Question1 ,
. . .
MAX(CASE WHEN Question = 1 THEN Comment END) AS CommentsQ1,
. . .
FROM Surveys
WHERE Question in (1,2,3)
GROUP BY Employee, surveyNo;