> But refreshing a materialized view doesn't only change relispopulated > but also columns like relfilenode, relpages, relhasindex, etc. Doesn't > changing these columns during REFRESH MATERIALIZED VIEW make your > optimization applicable in a lot less cases?
I don't think so. If we can skip SetMatViewPopulatedState(), we avoid generating a dead pg_class tuple in all cases. > I'm actually wondering why it works at all, even in the example you > gave. Because I thought that even when nothing has changed the pg_class > row is updated for more columns than just relispopulated. "refresh materialized view concurrently" is done by doing DELETE + INSERT to the matview directly, so only relispopulated will change before the patch. After the patch, the pg_class row don't change anymore. -- Regards, ChangAo Chen
