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To: Jon Nelson <jnelson+pgsql@jamponi.net>
cc: pgsql-performance@postgresql.org
Subject: Re: copy vs. C function 
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Comments: In-reply-to Jon Nelson <jnelson+pgsql@jamponi.net>
	message dated "Wed, 14 Dec 2011 08:06:09 -0600"
Date: Wed, 14 Dec 2011 10:25:30 -0500
Message-ID: <7080.1323876330@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
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Jon Nelson <jnelson+pgsql@jamponi.net> writes:
> Regarding caching, I tried caching it across calls by making the
> TupleDesc static and only initializing it once.
> When I tried that, I got:

> ERROR:  number of columns (6769856) exceeds limit (1664)

> I tried to find some documentation or examples that cache the
> information, but couldn't find any.

You might find reading record_in to be helpful.  What it caches is not
exactly what you need to, I think, but it shows the general principles.
There are lots of other functions that use fn_extra to cache info, too.

			regards, tom lane