Re: [INTERFACES] 8K query limit in 6.5?

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: Matthew Hagerty <matthew(at)venux(dot)net>
Cc: pgsql-interfaces(at)postgreSQL(dot)org
Subject: Re: [INTERFACES] 8K query limit in 6.5?
Date: 1999-07-13 16:42:50
Message-ID: 23455.931884170@sss.pgh.pa.us
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-interfaces

Matthew Hagerty <matthew(at)venux(dot)net> writes:
> ... please make this bigger! Or tell me how and I'll do it. :)

"Find all the places that need fixing, and fix 'em." :-)
The devil is in the details ... and there are a lot of details.
You could probably get some useful functionality just by fixing
frontend libpq's output buffer and the query input buffer in
backend/tcop/postgres.c. The trouble comes in cleaning up all the
details, like fixed-size buffers in COPY, pg_dump, etc etc etc etc.

Michael Ansley seems to be interested in working on this; I'd
suggest getting together with him if you want to help.

> Is it really such a big deal to increase the size of a query that pg can
> handle? I'm talking about the size of a query submitted to pg, from what I
> understand there is no limit on the record (tuple) size that can be
> returned from pg. Is my understanding correct?

There is a (quite unrelated) limit on the size of a tuple that can be
stored on disk, but AFAIK you can construct an arbitrarily large tuple
as the result of computations specified in a SELECT and it will be
passed back to your frontend application without trouble; as long as
you don't run out of memory on either side, that is.

Where we want to end up, of course, is no limit on the size of a disk
tuple either, but the code changes for that are almost entirely
unrelated to the ones that deal with the textual length of a query.
It's best tackled as two independent projects.

regards, tom lane

Browse pgsql-interfaces by date

  From Date Subject
Next Message Daren Sefcik 1999-07-13 16:50:17 RE: [INTERFACES] Three posts and no response 8--(
Previous Message Bradford F. Lyon 1999-07-13 16:34:07 sub