"Nigel J. Andrews" <nandrews(at)investsystems(dot)co(dot)uk> writes:
> However, since making some changes to my code I've not had time to do the
> investigation so I just thought I'd ask if there's been any reports on the
> relative speed of normal sql execution against prepared statements.
You can lose if the prepared statements are parameterized in such a way
that the planner can't see critical information. This has been hashed
over many a time in the pgsql-performance archives (though mostly in the
context of queries in plpgsql functions). Try EXPLAIN EXECUTE and see
if you get a materially different plan than with the straight query.
regards, tom lane