Question

SQL server 2016，子查询返回了多个值。

我运行以下查询：

Select word,
       tabl2.nowdatetime,
       tabl2.MAX_COUNT_ID,
       tabl2.MIN_COUNT_ID,
       tabl2.[border(%)],
       tabl2.id
From   (
           Select word,
                  tabl.nowdatetime,
                  tabl.id,
                  Cast(tabl.MAX_COUNT_ID As Float) As MAX_COUNT_ID,
                  Cast(tabl.MIN_COUNT_ID As Float) As MIN_COUNT_ID,
                  ((((Cast(tabl.MAX_COUNT_ID As Float)) - (Cast(tabl.MIN_COUNT_ID As Float))) / (Cast(tabl.MIN_COUNT_ID As Float))) * 100) As 'border(%)'
           From   (
                      Select Distinct word,
                             (
                                 Select Max(nowdatetime)
                                 From   Presign_Problem
                                 Where  nowdatetime >= DateAdd(Hour, -4, GetDate())
                             ) As nowdatetime,
                             (
                                 Select   Min(count_id)
                                 From     Presign_Problem pp2
                                 Where    pp1.word = pp2.word
                                          And nowdatetime >= DateAdd(Hour, -4, GetDate())
                                 Group By word
                             ) As MIN_COUNT_ID,
                             (
                                 Select   Max(count_id)
                                 From     Presign_Problem pp2
                                 Where    pp1.word = pp2.word
                                          And nowdatetime >= DateAdd(Hour, -4, GetDate())
                                 Group By word
                             ) As MAX_COUNT_ID,
                             (
                                 Select id
                                 From   Presign_Problem pp2
                                 Where  pp1.word = pp2.word
                                        And nowdatetime >= DateAdd(Hour, -4, GetDate())
                                        And count_id = (
                                                           Select Max(count_id)
                                                           From   Presign_Problem pp3
                                                           Where  pp1.word = pp3.word
                                                                  And nowdatetime >= DateAdd(Hour, -4, GetDate())
                                                       )
                             ) As id
                      From   Presign_Problem pp1
                      Where  nowdatetime >= DateAdd(Hour, -4, GetDate())
                  ) tabl
           Where  tabl.id Is Not Null
       ) tabl2;

我收到以下错误：

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。下面的错误：，（从Presign_Problem pp2中选择id，其中pp1.word = pp2.word和nowdatetime＆gt; = DATEADD（HOUR，-4，GETDATE（））和count_id =（SELECT MAX（count_id）FROM Presign_Problem pp3其中pp1.word = pp3。 word和nowdatetime＆gt; = DATEADD（HOUR，-4，GETDATE（））））作为id

以前，查询未显示错误。

以下是表中数据的示例：

word count_word count_id nowdatetime id 

computer 73 61 22.08.2017 15:24 ID23679381,ID48525000,ID23597299

computer 74 62 22.08.2017 14:24 ID23682019,ID23499955,ID23534359

computer 80 70 22.08.2017 12:24 ID23629307,ID48529530,ID23612836

有什么想法吗？我该如何解决？

Answer 1

试试这个

选择ID时使用Aggregate函数或TOP子句。

我在这里使用了TOP子句。

Select word,
       tabl2.nowdatetime,
       tabl2.MAX_COUNT_ID,
       tabl2.MIN_COUNT_ID,
       tabl2.[border(%)],
       tabl2.id
From   (
           Select word,
                  tabl.nowdatetime,
                  tabl.id,
                  Cast(tabl.MAX_COUNT_ID As Float) As MAX_COUNT_ID,
                  Cast(tabl.MIN_COUNT_ID As Float) As MIN_COUNT_ID,
                  ((((Cast(tabl.MAX_COUNT_ID As Float)) - (Cast(tabl.MIN_COUNT_ID As Float))) / (Cast(tabl.MIN_COUNT_ID As Float))) * 100) As 'border(%)'
           From   (
                      Select Distinct word,
                             (
                                 Select Max(nowdatetime)
                                 From   Presign_Problem
                                 Where  nowdatetime >= DateAdd(Hour, -4, GetDate())
                             ) As nowdatetime,
                             (
                                 Select   Min(count_id)
                                 From     Presign_Problem pp2
                                 Where    pp1.word = pp2.word
                                          And nowdatetime >= DateAdd(Hour, -4, GetDate())
                                 Group By word
                             ) As MIN_COUNT_ID,
                             (
                                 Select   Max(count_id)
                                 From     Presign_Problem pp2
                                 Where    pp1.word = pp2.word
                                          And nowdatetime >= DateAdd(Hour, -4, GetDate())
                                 Group By word
                             ) As MAX_COUNT_ID,
                             (
                                 Select TOP 1 id
                                 From   Presign_Problem pp2
                                 Where  pp1.word = pp2.word
                                        And nowdatetime >= DateAdd(Hour, -4, GetDate())
                                        And count_id = (
                                                           Select Max(count_id)
                                                           From   Presign_Problem pp3
                                                           Where  pp1.word = pp3.word
                                                                  And nowdatetime >= DateAdd(Hour, -4, GetDate())
                                                       )
                             ) As id
                      From   Presign_Problem pp1
                      Where  nowdatetime >= DateAdd(Hour, -4, GetDate())
                  ) tabl
           Where  tabl.id Is Not Null
       ) tabl2;

Answer 2

正如它在错误中所述，这个子查询：

Select id
From   Presign_Problem pp2
Where  pp1.word = pp2.word
    And nowdatetime >= DateAdd(Hour, -4, GetDate())
    And count_id = (
                       Select Max(count_id)
                       From   Presign_Problem pp3
                       Where  pp1.word = pp3.word
                              And nowdatetime >= DateAdd(Hour, -4, GetDate())

返回多个记录，在此上下文中不允许这样做。您需要id的单个值，但SQL Server并不知道从找到的多个值中选择正确的值。您需要修复数据（例如id只有唯一值）或更改此查询，以便只返回1条记录，并获得id的不同值（将DISTINCT添加到Select，使用聚合等）。

在不知道数据是什么的情况下，我们无法告诉您哪一个是最合适的选择。

SQL server 2016，子查询返回了多个值

2 个答案: