On Sun, Feb 02, 2020 at 03:18:19PM +0100, Marco Colli wrote: > Hello! > > Let's say that you have a simple query like the following on a large table > (for a multi-tenant application): > SELECT "subscribers".* FROM "subscribers" WHERE "subscribers"."project_id" > = 123 AND (tags @> ARRAY['de']::varchar[]); > > If you run EXPLAIN ANALYZE you can see that stats are completely wrong. > For example I get an expected count of 3,500 rows whereas the actual > result is 20 rows. This also results in bad query plans... https://www.postgresql.org/message-id/CAMkU%3D1z%2BQijUWAYgeqeyw%2BAvD7adPgOmEnY%2BOcTw6qDVFtD7cQ%40mail.gmail.com On Fri, Jan 10, 2020 at 12:12:52PM -0500, Jeff Janes wrote: > Why is the estimate off by so much? If you run a simple select, what the > actual and expected number of rows WHERE project_id = 12345? WHERE tags @> > '{crt:2018_11}'? Is one of those estimates way off reality, or is it only > the conjunction which is deranged? Could you respond to Jeff's inquiry ? Justin
