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williamdclttoday at 8:59 AM0 repliesview on HN

> > The optimizer is usually smarter than you think.

> Except for when it isn't, and moves heavy calculation inside a nested loop inside a nested loop to avoid an index scan. Nothing is perfect.

Yeah that's also been my experience. It's true that Postgres is usually smarter than I think, when I try to figure out why it's not using a better query plan I eventually find out that it wouldn't be better at all. But from time to time, it genuinely is taking a bad decision and having no power over that at all is a problem