On 8/23/24 09:51, Adrian Klaver wrote:
On 8/23/24 09:33, Matthew Tice wrote:
On Fri, Aug 23, 2024 at 10:26 AM Adrian Klaver
<adrian.klaver@xxxxxxxxxxx <mailto:adrian.klaver@xxxxxxxxxxx>> wrote:
https://www.postgresql.org/docs/current/pgstattuple.html
<https://www.postgresql.org/docs/current/pgstattuple.html>
pgstattuple_approx(regclass) returns record
pgstattuple_approx is a faster alternative to pgstattuple that
returns approximate results.
Not sure how you get exact count out of that?
Maybe the wording is a little confusing to me. Under the section
for pgstattuple_approx:
"pgstattuple_approx tries to avoid the full-table scan and returns
exact dead tuple statistics along with an approximation of the number
and size of live tuples and free space."
Yeah, see what you mean.
The part that bears more investigating for this case is:
"It does this by skipping pages that have only visible tuples according
to the visibility map (if a page has the corresponding VM bit set, then
it is assumed to contain no dead tuples).
Wondering if PostgreSQl-compatible covers this?
Meant to add:
What happens if you use pgstattuple instead?
--
Adrian Klaver
adrian.klaver@xxxxxxxxxxx
