Re: [HACKERS] Bug on complex join

On Sat, 6 Mar 1999, Vadim Mikheev wrote:

> Oleg Broytmann wrote:
> > 
> > Hi!
> > 
> >    I am continuing playing with the query (I reduced it to):
> > SELECT  sh.distr_id , d.distr_id
> >    FROM central cn, shops sh, districts d
> >       WHERE cn.shop_id = sh.shop_id
> > 
> > and got 27963 rows. I filtered it out (with awk:) where $1 == $2 (1st
> > column is equal to second) and got 3104 rows.
> > 
> >    But the query
> > SELECT d.*
> >    FROM central cn, shops sh, districts d
> >       WHERE cn.shop_id = sh.shop_id AND sh.distr_id = d.distr_id
> > 
> > returned 0 rows.
> > 
> >    Where is the bug?
> 
> Please post me EXPLAIN VERBOSE for second query.


EXPLAIN VERBOSE SELECT d.*   FROM central cn, shops sh, districts d      WHERE cn.shop_id = sh.shop_id AND sh.distr_id
=d.distr_id
 
;
pqReadData() -- backend closed the channel unexpectedly.This probably means the backend terminated abnormally before or
whileprocessing the request.
 
We have lost the connection to the backend, so further processing is impossible.  Terminating.
  :(((

> Vadim
> 

Oleg.
----    Oleg Broytmann     http://members.xoom.com/phd2/     phd2@earthling.net          Programmers don't die, they
justGOSUB without RETURN.