| From: | Richard Guo <guofenglinux(at)gmail(dot)com> |
|---|---|
| To: | Haibo Yan <tristan(dot)yim(at)gmail(dot)com> |
| Cc: | Pg Hackers <pgsql-hackers(at)lists(dot)postgresql(dot)org> |
| Subject: | Re: Fix CPU cost of right-semi and right-anti hash joins |
| Date: | 2026-08-24 08:35:22 |
| Message-ID: | CAMbWs4_Nb9-uL==RAU9aOcG-xWY897wMXML_9SoPR6bCCDhUvA@mail.gmail.com |
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| Lists: | pgsql-hackers |
On Sat, Aug 22, 2026 at 2:15 AM Haibo Yan <tristan(dot)yim(at)gmail(dot)com> wrote:
> One small testing point: the new hj_small/hj_large cases have no non-hash
> joinqual, so qp_qual_cost.per_tuple is zero and they don’t exercise the new
> v4 branch.
> Also the test comment saying cpu_tuple_cost and qp_qual_cost are both charged
> on inner-side rows is no longer quite true for RIGHT_ANTI in v4.
Right. Fixed.
Attached is v5 of this patch. I plan to push it soon if there are no
objections. It can result in plan changes, so I don't plan to
back-patch it to stable branches. I once thought about pushing it to
v19, but at this late phase of the v19 cycle I'm inclined not to.
Maybe I would have done that if it were June.
Any thoughts are welcome.
- Richard
| Attachment | Content-Type | Size |
|---|---|---|
| v5-0001-Fix-CPU-cost-of-right-semi-and-right-anti-hash-jo.patch | application/octet-stream | 26.6 KB |
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