Jeff Janes wrote:
I think what I would do next is EXPLAIN (without ANALYZE) one of the
queries repeatedly, say once a second, while the other query either
runs or doesn't run repeatedly, that is the other query runs for 11
minutes (or however it takes to run), and then sleeps for 11 minutes
in a loop. Then you can see if the explain plan differs very
reliably, and if the transition is exactly aligned with the other
starting and stopping or if it is offset.
Hi Jeff,
I ran the one analyze over and over again as you proposed - but the
result never changed.
But I think I found a solution for the problem. While browsing through
the manual I found a statement about GIN indexes:
"For tables with GIN indexes, VACUUM (in any form) also completes any
pending index insertions, by moving pending index entries to the
appropriate places in the main GIN index structure". I use a gist and no
gin index, but I tried to vacuum the (freshly filled) table, and it
helped. It seems that the planer is simply not aware of the existence of
the index although I run an analyze on the table right before the query.
Thank you all for your suggestions!
Jan
