| From: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
|---|---|
| To: | |
| Cc: | David Rowley <dgrowleyml(at)gmail(dot)com>, Richard Guo <guofenglinux(at)gmail(dot)com>, nikhil raj <nikhilraj474(at)gmail(dot)com>, pgsql-hackers(at)lists(dot)postgresql(dot)org |
| Subject: | Re: Significant Execution Time Difference Between PG13.14 and PG16.4 for Query on information_schema Tables. |
| Date: | 2024-08-27 23:37:56 |
| Message-ID: | 3159017.1724801876@sss.pgh.pa.us |
| Views: | Whole Thread | Raw Message | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-general pgsql-hackers |
I wrote:
> That seems like a pretty fishy way to do it. Are you saying that
> Memoize is never applicable if there aren't outer joins in the
> query? Without OJs there probably won't be any PHVs.
Oh, scratch that, I see you mean this is an additional way to do it
not the only way to do it. But I'm confused why it works for
t1.two+1 AS c1
but not
t1.two+t2.two AS c1
Those ought to look pretty much the same for this purpose.
regards, tom lane
| From | Date | Subject | |
|---|---|---|---|
| Next Message | David Rowley | 2024-08-27 23:57:53 | Re: Significant Execution Time Difference Between PG13.14 and PG16.4 for Query on information_schema Tables. |
| Previous Message | Tom Lane | 2024-08-27 23:15:21 | Re: Significant Execution Time Difference Between PG13.14 and PG16.4 for Query on information_schema Tables. |
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Peter Geoghegan | 2024-08-27 23:41:43 | Re: Showing primitive index scan count in EXPLAIN ANALYZE (for skip scan and SAOP scans) |
| Previous Message | Matthias van de Meent | 2024-08-27 23:22:20 | Re: Showing primitive index scan count in EXPLAIN ANALYZE (for skip scan and SAOP scans) |