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A comment on Show HN: PostgreSQL Index Advisor. Parent comment

Re:Show HN: PostgreSQL Index Advisor by Scene_Cast2 on Sunday April 14, 2024 @02:10PM (#40033079)
One example is that in Presto, joins assume that left (IIRC) table is the big one you stream, and the right one is the small one you hash. One of the newer features was that in some cases, the optimizer is able to ignore the SQL order and correctly pick which table to hash and which one to stream.
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Re:Show HN: PostgreSQL Index Advisor by legulere on Sunday April 14, 2024 @03:51PM (#40033869)
Isn't that just basic table/index statistics to know which table is the smallest?
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Re:Show HN: PostgreSQL Index Advisor by Scene_Cast2 on Sunday April 14, 2024 @08:49PM (#40035926)
Not if you're joining on a filtered table or a result of another join.
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