Question

我试图计算与联接中由ParentID联接的PostID相关的所有帖子的计数，但是我得到一个错误，所以当我按照所有的字段进行分组时，我仍然得到错误： - 错误在< / p>

SELECT s.Level, s.Sequence, s.PostID, s.AddedBy,  
s.Title, s.ParentID, s.Path_String, 
Owner = COALESCE(o.AddedBy, s.AddedBy), COUNT(r.ParentID)
FROM cte AS s 
LEFT OUTER JOIN cte AS o 
ON s.ParentID = o.PostID 
RIGHT join cte AS r
on s.PostID = r.ParentID
ORDER BY s.Sequence;

PostID，ParentID，AddedBy，Title，Path_String： - PostID是IdentityColumn Path_String的格式为1 /，1/1 /，1/1/2，ParentID是整数

这是我的第一个结果的代码：

SELECT s.Level, s.Sequence, s.PostID, s.AddedBy,  
s.Title, s.ParentID, s.Path_String, 
Owner = COALESCE(o.AddedBy, s.AddedBy), COUNT(r.ParentID)
FROM cte AS s 
LEFT OUTER JOIN cte AS o 
ON s.ParentID = o.PostID 
join cte AS r
on s.PostID = r.ParentID

GROUP BY s.Level, s.Sequence, s.PostID, s.AddedBy, s.Title, s.ParentID, s.Path_String, COALESCE  (o.AddedBy, s.AddedBy)
ORDER BY s.Sequence; 



    Level       Sequence                    PostID      AddedBy    Title     ParentID    Path_String  Owner    Count

1     00000003                          3           kirkdm     test      NULL        3/           kirkdm   1
2     0000000300000005                  5           MikeDM     re: test  3           3/5/         kirkdm   2
3     000000030000000500000008          8           Joelene    re: test  5           3/5/8/       MikeDM   2
3     000000030000000500000009          9           kirkdm     re: test  5           3/5/9/       MikeDM   1
4     00000003000000050000000900000010  10          Crushanin  re: test  9           3/5/9/10/    kirkdm   1

应该是带有回复列的列这是我的第二个结果的代码我想得到子计数的第二个结果：

SELECT s.Level, s.Sequence, s.PostID, s.AddedBy,  
s.Title, s.ParentID, s.Path_String, 
Owner = COALESCE(o.AddedBy, s.AddedBy)
FROM cte AS s 
LEFT OUTER JOIN cte AS o 
ON s.ParentID = o.PostID 
ORDER BY s.Sequence; 

Level       Sequence                                     PostID      AddedBy      Title     ParentID    Path_String     Owner     Count Children of Replies here

1           00000003                                     3           kirkdm       test      NULL        3/              kirkdm
2           0000000300000005                             5           MikeDM       re: test  3           3/5/            kirkdm
3           000000030000000500000008                     8           Joelene      re: test  5           3/5/8/          MikeDM
4           00000003000000050000000800000014             14          Christian    re: test  8           3/5/8/14/       Joelene
4           00000003000000050000000800000015             15          Zeke         re: test  8           3/5/8/15/       Joelene
3           000000030000000500000009                     9           kirkdm       re: test  5           3/5/9/          MikeDM
4           00000003000000050000000900000010             10          Crushanin    re: test  9           3/5/9/10/       kirkdm
5           0000000300000005000000090000001000000011     11          Tim          re: test  10          3/5/9/10/11/    Crushanin

Answer 1

添加group by子句。

group by s.Level, s.Sequence, s.PostID, s.AddedBy, s.Title, s.ParentID, s.Path_String, COALESCE(o.AddedBy, s.AddedBy)

得到一个儿童加入条款的计数

1 个答案: