On 8 June 2012 11:58, Albe Laurenz <laurenz.albe@xxxxxxxxxx> wrote: > Did you take caching of table data in the buffer cache or the filesystem > cache into account? Did you run your tests several times in a row and > were the actual execution times consistent? Yes, and yes. >> Would tweaking enable_seqscan and other planner functions during the >> CREATE FUNCTION have an effect on the stored plan? > > No, but you can use the SET clause of CREATE FUNCTION to change > enable_seqscan for this function if you know that this is the right > thing. > But be aware that things might be different for other function arguments > or when the table data change, so this is normally considered a bad > idea. Ok. >> Do the functions need to be re-created when the database is fully >> populated, to adjust their stored plans with regards to new > selectivity >> situation on the indexes? > > No. Even in PL/pgSQL, where plans are cached, this is only for the > lifetime of the database session. The plan is generated when the > function is called for the first time in a database session. Thanks for clearing this up for me! I thought SQL functions are also pre-planned and that the plans are static. -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
