Re: Performance degradation with CTEs, switching from PG 11 to PG 15

Am 22.11.23 um 12:38 schrieb Jean-Christophe Boggio:
>
>
> Also, adding "materialized" to both "withcwrack" and "withcwrack0" 
> CTEs gets the result in acceptable timings (a few seconds). The 
> problem with this is that we have some clients with older versions of 
> PG and I guess blindly adding the "materialized" keyword will cause 
> errors.
>

yeah, prior to 11 CTEs are a optimizer barrier. You can try to rewrite 
the queries to not using CTEs - or upgrade. If i were you i would upgrade.


Regards, Andreas

-- 
Andreas Kretschmer - currently still (garden leave)
Technical Account Manager (TAM)
www.enterprisedb.com