From: Tom Lane <tgl@sss.pgh.pa.us>
To: Dave Cramer <davecramer@postgres.rocks>
cc: pgchem pgchem <pgchem@tuschehund.de>,
        "pgsql-interfaces@postgresql.org" <pgsql-interfaces@postgresql.org>
Subject: Re: C trigger significantly slower than PL/pgSQL?
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Comments: In-reply-to Dave Cramer <davecramer@postgres.rocks>
	message dated "Wed, 12 Apr 2023 08:03:41 -0400"
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Date: Wed, 12 Apr 2023 08:19:15 -0400
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Dave Cramer <davecramer@postgres.rocks> writes:
> Fair. So to answer your question. The C function should be faster.

If we exclude basic coding errors (i.e. not really "equivalent"
processing) then a possible theory is that plpgsql is being careful
to cache a query plan that your C code is causing to be recomputed
each time.  But yeah, all else being equal plpgsql should be slower.

			regards, tom lane