Обсуждение: regd count(count(*)) in group by

Hi,

We have a query "select count(count(*)) from test group by
trunc(test_date)". This works fine with Oracle but when moving to postgres I
changed it to "select count(count(*)) from test group by date_trunc('day',
test_date)" but I get the following error

ERROR:  Aggregate function calls may not be nested

Can some one help me...

Thanks
Yuva

Try this:

SELECT count(*) FROM (SELECT count(*)FROM testGROUP BY date_trunc('day', test_date)) as qry;


On Fri, 2002-07-26 at 16:03, Yuva Chandolu wrote:
> Hi,
> 
> We have a query "select count(count(*)) from test group by
> trunc(test_date)". This works fine with Oracle but when moving to postgres I
> changed it to "select count(count(*)) from test group by date_trunc('day',
> test_date)" but I get the following error
> 
> ERROR:  Aggregate function calls may not be nested
> 
> Can some one help me...
> 
> Thanks
> Yuva
> 
> ---------------------------(end of broadcast)---------------------------
> TIP 5: Have you checked our extensive FAQ?
> 
> http://www.postgresql.org/users-lounge/docs/faq.html
> 

On 26 Jul 2002, Rod Taylor wrote:

> Try this:
>
> SELECT count(*)
>   FROM (
>     SELECT count(*)
>     FROM test
>     GROUP BY date_trunc('day', test_date)
>     ) as qry;

Or this:
SELECT COUNT(*)FROM (    SELECT DISTINCT(date_trunc('day', test_date))    FROM test);

Matthew.