Re: [HACKERS] How to change order sort of table in HashJoin

Thanks for reply, sir. On 11/21/2016 1:39 AM, Tom Lane wrote: Man writes: Additional information. In 9.6 the second table (lesser tuple) was choosen (the same testdata). There are something (cost estimation?) different in previous versions. I'd bet on different

Re: [HACKERS] How to change order sort of table in HashJoin

Man writes: > Additional information. > In 9.6 the second table (lesser tuple) was choosen (the same testdata). > There are something (cost estimation?) different in previous versions. I'd bet on different statistics in the two installations (either you forgot to ANALYZE,

Re: [HACKERS] How to change order sort of table in HashJoin

Thanks for response, sir. On 11/20/2016 1:18 AM, Tom Lane wrote: Man Trieu writes: As in the example below, i think the plan which hash table is created on testtbl2 (the fewer tuples) should be choosen. The planner usually prefers to hash on the table that has a flatter

Re: [HACKERS] How to change order sort of table in HashJoin

Man Trieu writes: > As in the example below, i think the plan which hash table is created on > testtbl2 (the fewer tuples) should be choosen. The planner usually prefers to hash on the table that has a flatter MCV histogram, since a hash table with many key collisions will