I wrote:
> I will take another look at it now that you have the results of
> EXPLAIN ANALYZE posted
Could you run this?:
set work_mem = '50MB';
set effective_cache_size = '3GB';
EXPLAIN ANALYZE <your query>
begin transaction;
drop index node_comment_statistics_node_comment_timestamp_idx;
EXPLAIN ANALYZE <your query>
rollback transaction;
The BEGIN TRANSACTION and ROLLBACK TRANSACTION will prevent the index
from actually being dropped; it just won't be visible to your query
during that second run. I'm kinda curious what plan it chooses
without it.
Some configuration options can be dynamically overridden for a
particular connection. This is not a complete list of what you might
want to use in your postgresql.conf file, but it might turn up an
interesting plan for diagnostic purposes.
-Kevin