Re: sql question regarding count(*)

On Friday 07 March 2003 11:41 am, Stephan Szabo wrote:
> On Fri, 7 Mar 2003, Rajesh Kumar Mallah wrote:
> > Tomasz did you notice the two queries are totally differet on different
> > tables?
>
> A count() on a non-grouped table returns 1 row.
>
> A grouped table returns 1 row per group.  If there are no groups, no rows
> are returned.  If the groups are filtered by a having clause, it might
> also return no rows.

True the second query does not return any row.
even in first case no rows are returned.

where is the difference?

tradein_clients=# select userid from users where userid=-1;
+--------+
| userid |
+--------+
+--------+
(0 rows)

Time: 846.86 ms
tradein_clients=#


Regds
Mallah

----------------------------------------
Rajesh Kumar Mallah,
Project Manager (Development)
Infocom Network Limited, New Delhi
phone: +91(11)6152172 (221) (L) ,9811255597 (M)

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