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by SnowHill9902 1410 days ago
Can you give more information about your JOINs performance? It’s mostly dependent on the presence and optimization of INDEXes and cardinality as you mention. JOIN ON indexed integers is usually fastest.
1 comments

It’s not such an easy thing to describe.

Yes we join on indexed integers too.

The thing is, we believe as the amount of data changes the planner will give different instructions. Even after lots of analyzing and vacuuming.

It’s happened so many times and so randomly and because of growth we really have to re-examine joins that were very fast 6 months ago that are now really slow.