分组不在Oracle工作 -

Question

当我运行以下查询时，它可以正常工作

select  TO_CHAR(mydate ,'YYYYMMDD') , count(*) from table
where columnA = '123'
group by TO_CHAR(mydate,'YYYYMMDD')

但是当我尝试order by失败时

select  TO_CHAR(mydate ,'YYYYMMDD') , count(*) from table
where columnA = '123'
group by TO_CHAR(mydate,'YYYYMMDD')
order by mydate desc

同样当我尝试在日期做任何算术时，我得到同样的错误。

select  TO_CHAR(mydate +10/24 ,'YYYYMMDD') , count(*) from table
where columnA = '123'
group by TO_CHAR(mydate,'YYYYMMDD')
order by mydate desc

有人可以建议什么是最好的订购方式并添加10小时？

Answer 1

试试这个：

select  TO_CHAR(mydate ,'YYYYMMDD')  from table
where columnA = '123'
group by TO_CHAR(mydate,'YYYYMMDD')
order by mydate desc

即，您需要将select的所有列都放在group by中以使其正常工作。

修改： -

select  TO_CHAR(mydate ,'YYYYMMDD') , count(someID) from table
where columnA = '123'
group by TO_CHAR(mydate,'YYYYMMDD')
order by mydate desc
having count(someID)>1