| From: | Alexander Kuzmenkov <a(dot)kuzmenkov(at)postgrespro(dot)ru> |
|---|---|
| To: | Thomas Munro <thomas(dot)munro(at)enterprisedb(dot)com> |
| Cc: | David Rowley <david(dot)rowley(at)2ndquadrant(dot)com>, PostgreSQL-development <pgsql-hackers(at)postgresql(dot)org> |
| Subject: | Re: Removing unneeded self joins |
| Date: | 2018-08-03 16:49:47 |
| Message-ID: | 2285d5d0-f330-e8b6-9ee5-b2b90e44409b@postgrespro.ru |
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| Lists: | pgsql-hackers |
On 07/29/2018 01:42 PM, Thomas Munro wrote:
>
> I think you need to disable the optimisation when there is a locking
> clause on one side. Maybe it could be allowed if it's on both sides?
> Not sure.
Hi Thomas,
Thanks for testing. I think it should be OK to remove the join if the
row marks for both sides have the same type. I added the code to check
for that.
> You can't declare a variable here in C89.
>
Fixed.
--
Alexander Kuzmenkov
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company
| Attachment | Content-Type | Size |
|---|---|---|
| 0001-Remove-unique-self-joins-v4.patch | text/x-patch | 49.8 KB |
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