On 2017-10-24 17:18, Justin Pryzby wrote: > You could (re)install PG96 alongside PG10 and run a copy of the DB (even from > your homedir, or on a difference server) and pg_dump |pg_restore the relevant > tables (just be sure to specify the alternate host/port/user/etc as needed for > the restore invocation). I considered that but it is far too expensive just for getting the old query plan. The database is more than 1 TB big and replaying it from a dump to another server took us several days, primarily due to the heavy use of materialized views that are calculated over all rows of some large tables. As long as there is no safe pg_downgrade --link I'd rather keep trying to improve query performance on the current version. -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance