BUG #1753: Query Optimizer does not work well with libpg / PQexecParams - Mailing list pgsql-bugs

From Ernst Bachmann
Subject BUG #1753: Query Optimizer does not work well with libpg / PQexecParams
Date
Msg-id 20050705090906.3DC5CF0B0E@svr2.postgresql.org
Whole thread Raw
Responses Re: BUG #1753: Query Optimizer does not work well with libpg  (Oliver Jowett <oliver@opencloud.com>)
List pgsql-bugs
The following bug has been logged online:

Bug reference:      1753
Logged by:          Ernst Bachmann
Email address:      e.bachmann@xebec.de
PostgreSQL version: 8.0.3
Operating system:   Linux
Description:        Query Optimizer does not work well with libpg /
PQexecParams
Details:

It looks like the query optimizer isn't taking the value of parameters sent
with PQexecParams into account, thus generating (in my case, very) unoptimal
plans

There is a warning about that for "PREPARE", but with PQexecParams, the
parameter values should be available immediatly for the planner.

Sending the parameters inline in the SQL query string solved the problem for
me (Query executes in 5 ms instead of 500+), but thats obviously not my
favorite solution.

Is this something planned to be fixed, otherwise a warning in the libpq
documentation about "PQexecParams" being potentially slow would be nice.

Thanks
/Ernst

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