I've got 3 tables:
objects (object_id integer primary ...)
projects (project_id integer primary ...)
in the 3rt table I store an m:n relation
obj_2_proj (object_fk, project_fk, access_ts timestamp, primary
key (object_fk, project_fk))
Now I need to know the projekt and access_ts of all those objekt_fk with
the highest access_ts.
This highest access_ts might be NULL.
SELECT object_fk, project_fk, max(access_ts)
GOUP BY object_fk;
Postgres doesnt like this and complains, I had to include project_fk in
the GROUP BY but if I do this I get every line out of this table since
(object_fk, project_fk) is the primary key.
What to do?
pgsql-novice by date
|Next:||From: Brian Hurt||Date: 2008-02-11 19:10:38|
|Subject: Memory-leak-like effect on insane query (postgres 8.1.6)|
|Previous:||From: Charley Tiggs||Date: 2008-02-09 04:22:30|
|Subject: Re: sync two databases|