Question

此时正在使用的查询：

update metrics.time_created 
set cumu_count = (
    select count(*) 
    from perf_stats.time 
    where date(insert_datetime)='2015-12-18'
) 
where id=max(id);

我得到了＆＃34;无效使用群组功能＆＃34;在这里 - 我怎样才能重写这个以保持相同的逻辑？我必须更新metrics.time_created表中的最新行。

Answer 1

试试这个：

update metrics.time_created a
set cumu_count = (
  select count(*) 
  from perf_stats.time 
  where date(insert_datetime)='2015-12-18'
) 
where exists (
  select 1
  from (select max(id) as maxid from metrics.time_created) t
  where maxid = a.id
);

示例演示：http://sqlfiddle.com/#!9/6bc3cd/1

编辑：

根据评论，这里有改变

update metrics.time_created a

set cumu_count = 
(
  select count(*) 
  from perf_stats.time pt
  where exists
  (
    select 1
    from (select max(curr_date) as mcd from metrics.time_created) x
    where mcd = date(insert_datetime)
  )
) 

where exists 
(
  select 1
  from (select max(id) as maxid from metrics.time_created) t
  where maxid = a.id
);

示例演示：http://sqlfiddle.com/#!9/fcc91a/1

Answer 2

你可以使用这样的自联接：

update metrics.time_created as t1
inner join (
    select max(id) as id 
    from metrics.time_created
) as t2 on t1.id = t2.id
set cumu_count = (
  select count(*) 
  from perf_stats.time 
  where date(insert_datetime)='2015-12-18'
)

Answer 3

如果您尝试使用最大If My.Computer.FileSystem.DirectoryExists("C:\WINDOWS\Microsoft.NET\Framework\v4.0.30319") Then 'do something End If更新一行，则可以使用Sub firstValueOfColumn() Dim dColumn As Long Cells.Select For Each tCell In Selection If tCell = 0.650833312 Then dColumn = tCell.Column tCell.Select If Cells(1, dColumn) = "" Then MsgBox Cells(1, dColumn).End(xlDown).Value Else MsgBox Cells(1, dColumn).Value End If Exit For End If Next End Sub和id：

order by

需要重写查询以在where子句中使用max函数

3 个答案: