| 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 |
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| 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
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