I'm having problems with another one of my queries after moving from 8.1.19 to 8.4.2. On 8.1.19, the plan looked like this:
That runs pretty well. On 8.4.2, the same query looks like this:
If I turn off mergejoin and hashjoin, I can get 8.4.2 to spit out this:
...which it thinks is going to suck but which does not.
The query and relevant table definitions are here:
Any suggestions? I'm guessing the problem is with the absurd over-estimation on the nested loop under the sort node, but I'm not sure why it's so bad.
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