Re: Getting non_NULL right-side values on a non-matching join? - Mailing list pgsql-general

From Tom Lane
Subject Re: Getting non_NULL right-side values on a non-matching join?
Date
Msg-id 16923.1385101905@sss.pgh.pa.us
Whole thread Raw
In response to Re: Getting non_NULL right-side values on a non-matching join?  (Ken Tanzer <ken.tanzer@gmail.com>)
Responses Re: Getting non_NULL right-side values on a non-matching join?
List pgsql-general
Ken Tanzer <ken.tanzer@gmail.com> writes:
> Getting a build environment together seemed more painful, so here's a test
> case.

Wow, that's pretty broken.  I'll dig into it tomorrow.

> Just for fun, I tried this in another database on a different
> machine (and with 9.0.08).  I got the same results, so it doesn't seem to
> be a case of something wacky with my particular database.

Yeah, seems to fail the same way in all active branches ...

> p.s.,  Not your problem I know, but I need to deal with this somehow and
> rather soon.

If you just need a work-around-it-right-now solution, I'd suggest
introducing an "OFFSET 0" optimization fence into one or another of the
levels of view below the outer joins.  I've not experimented but I think
that ought to fix it, at some possibly-annoying cost in query
optimization.  Hopefully I'll have another answer tomorrow.

            regards, tom lane


pgsql-general by date:

Previous
From: Ken Tanzer
Date:
Subject: Re: Getting non_NULL right-side values on a non-matching join?
Next
From: Andreas Joseph Krogh
Date:
Subject: Performance of Blobs, LargeObject