GROUP BY正在返回错误的值？

Question

我已经写了下面的查询，但它没有在日期上正确分组，并返回2行，实际上应该由GROUP BY合并为一行。

select i.overridedate, 
     month(i.Overridedate), 
     count(i.id)as count, 
     sum(case when oi.rating <50 then 1 else 0 end) as unfav, 
     sum(case when oi.Rating =50 then 1 else 0 end) as neu, 
     sum(case when oi.Rating >50 then 1 else 0 end) as fav, 
     avg(oi.Rating)as 'Av Rating' 
from Items i (nolock) 

inner join ItemOrganisations oi (nolock) on i.ID= oi.ItemID 
inner join Lookup_ItemTypes it (nolock) on it.ID = i.ItemTypeID 
inner join Batches b (nolock) on b.ID=i.BatchID 
inner join Lookup_ItemStatus lis (nolock) on lis.ID = i.StatusID 
inner join Lookup_BatchStatus lbs (nolock) on lbs.ID = b.StatusID 
inner join Lookup_BatchTypes bt on bt.id = b.Typeid 

where lbs.Name = 'Completed by Analyst' 
     or lbs.Name='Delivered/Imported into Neptune Online' 
     and lis.Name = 'Complete' 
     and i.IsRelevant = 1 
     and bt.Name = 'Live' 
    group by i.overridedate, Month(i.OverrideDate) 
    having i.OverrideDate between '2012-07-01 00:00:00.000' and '2012-09-30 00:00:00.000' 

正如你所看到的，最后两行代表了7个月的数据不会被分组：

NULL  NULL    1  0  1  0  1  55 
2013-01-03 00:00:00.000  1  1  1  0  0  10 
2012-05-28 00:00:00.000  5  7  1  0  1  50 
2012-06-01 00:00:00.000  6  7  1  0  0  20 
2012-07-10 00:00:00.000  7  1  0  0  0  NULL 
2012-07-11 00:00:00.000  7  8  1  0  6  66 

Answer 1

的group by是正确的。你为什么在其中包含重写日期？

也许你的选择应该是：

select min(i.overridedate), month(i.Overridedate), 
. . . 
group by month(i.Overridedate) 

而且，我坚决与说，包括当年的评论一致认为：

select min(i.overridedate), year(i.Overridedate), month(i.Overridedate), 
. . . 
group by year(i.Overridedate), month(i.Overridedate)