2016-09-01 11:53 GMT+12:00 Venkata B Nagothi <nag1...@gmail.com>: > > On Thu, Sep 1, 2016 at 8:41 AM, Patrick B <patrickbake...@gmail.com> > wrote: > >> Hi guys, >> >> A dev has ran a VACUUM FULL command into our test database running >> PostgreSQL 9.5 (I know... goddamn!!!!)... >> >> ... after the Vacuum Full, some queries start using SEQ scans instead of >> indexes... >> >> Does that happen because of the size of the table? The table that I'm >> referring to is 150MB big after the vacuum (Before was 1G)... >> > > Yes, it is possible that sequential scans after vacuum full are cheaper > than Index scans before vacuum full ? do you see improvement in query > response times ? > How does the cost differ ? > > Regards, > Venkata B N > > Fujitsu Australia >
Well... the response time was worst than when using index.. that's very weird... I've re-created the indexes now a ran ANALYZE and the query is using again the index.. just wanted understand what happened...
