Re: [EXT] Re: Improve "select count(*)" query - takes more than 30 mins for some large tables - Mailing list pgsql-admin
Laurenz,
Oh really? Even if it did an INDEX ONLY SCAN, it would still be slower because it still has to access the heap in a random I/O kinda way (like I said-->"The heap always gets accessed for select counts") because visibility info is only found in the HEAP not the index.
Laurenz Albe wrote on 7/12/2022 3:13 PM:
Oh really? Even if it did an INDEX ONLY SCAN, it would still be slower because it still has to access the heap in a random I/O kinda way (like I said-->"The heap always gets accessed for select counts") because visibility info is only found in the HEAP not the index.
Laurenz Albe wrote on 7/12/2022 3:13 PM:
I'd say that both statements are wrong:
Regards,
Michael Vitale
703-600-9343
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