Date: Mon, 7 Jul 2003 09:23:39 -0700 (PDT)
From: Stephan Szabo <sszabo@megazone23.bigpanda.com>
To: markus brosch <brosch@gmx.de>
Cc: pgsql-sql <pgsql-sql@postgresql.org>
Subject: Re: max length of sql select statement ?
In-Reply-To: <1057592658.881.93.camel@sam>
Message-ID: <20030707091855.O77173-100000@megazone23.bigpanda.com>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII


On 7 Jul 2003, markus brosch wrote:

> I was searching the archive and was wondering why nobody asked this
> strange(!) question (or I've not found it?):
>
> "What is the max allowed length of a sql statement or query?"

AFAIR in recent versions it's effectively limited only by resources (how
much bandwidth/memory do you want to use).

> I want to combine hundrets or thousands 'OR' within a select statement.
> Possible or not (e.g: SELECT * FROM table WHERE col='a' OR col='b' OR
> col='c' OR ...... )

It should be possible.

> This would be a very "dirty" or some would say, a "horrible" solution;
>
> but how are you searching through your table with sql, when your SELECT
> is against a collection of different elements (e.g. Array of Strings,
> which should fit on one column and return all records which fit)

Are the 'a', 'b', etc... fixed or generated on the fly?  I'm not sure
that the plan for a thousand OR clauses (or equivalently a thousand
entries in a static IN) is going to necessarily be terribly good.  You
might have better luck setting it up to do a join with a table (possibly a
temporary table if they're generated on the fly).