plan time of MASSIVE partitioning ...
Hans-Jürgen Schönig <postgres@cybertec.at>
From: PostgreSQL - Hans-Jürgen Schönig <postgres@cybertec.at>
To: pgsql-hackers Hackers <pgsql-hackers@postgresql.org>
Date: 2010-09-03T09:40:37Z
Lists: pgsql-hackers
hello everybody, we came across an issue which turned out to be more serious than previously expected. imagine a system with, say, 1000 partitions (heavily indexed) or so. the time taken by the planner is already fairly heavy in this case. i tried this one with 5000 unindexed tables (just one col): test=# \timing Timing is on. test=# prepare x(int4) AS select * from t_data order by id desc; PREPARE Time: 361.552 ms you will see similar or higher runtimes in case of 500 partitions and a handful of indexes. does anybody see a potential way to do a shortcut through the planner? a prepared query is no solution here as constraint exclusion would be dead in this case (making the entire thing an even bigger drama). did anybody think of a solution to this problem. or more precisely: can there be a solution to this problem? many thanks, hans -- Cybertec Schönig & Schönig GmbH Gröhrmühlgasse 26 A-2700 Wiener Neustadt, Austria Web: http://www.postgresql-support.de