From: | "Josh Berkus" <josh(at)agliodbs(dot)com> |
---|---|
To: | Joseph Shraibman <jks(at)selectacast(dot)net> |
Cc: | pgsql-sql(at)postgresql(dot)org |
Subject: | Re: count() and multiple tables |
Date: | 2001-03-19 23:52:27 |
Message-ID: | web-26888@davinci.ethosmedia.com |
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Thread: | |
Lists: | pgsql-sql |
Joseph,
SImple as pie (e.g., easy on your 100th one):
> select count(*) from d where status = 2 and d.id = u.dkey and
> u.status =
> 2 and not u.b and u.akey = a.key and a.status = 3;
Count(*) will always count the number of records in the largest table in
your join. If you want the number of records in a specific table, then
you have to make sure that that table is the only on in your FROM
clause, and reference all other tables in WHERE:
select count(*) from d
where id IN (select u.dkey from u, a
where u.akey = a.key
AND u.status = 2 and not u.b
and a.status = 3);
-Josh Berkus
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Josh Berkus
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