Re: [EXT] Re: Improve "select count(*)" query - takes more than 30 mins for some large tables

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:

I'd say that both statements are wrong:

Regards,

Michael Vitale

Michaeldba@sqlexec.com

703-600-9343