Allen,
> I had no idea analyze was playing such a big role in this sense.. I really
> thought that other than saving space, it wasn't doing much for tables that
> don't have indexes on the.
Among other things, ANALYZE tells postgres how many rows are in the table. So
if you add a PK constraint after loading 10 million rows without ANALYZE,
PostgreSQL is likely to think that there is only one row in the table ... and
choose a nested loop or some other really inefficient method of checking for
uniqueness.
--
Josh Berkus
Aglio Database Solutions
San Francisco
