Re: Processing long AND/OR lists - Mailing list pgsql-hackers

From Gurjeet Singh
Subject Re: Processing long AND/OR lists
Date
Msg-id CABwTF4X1ZifHC6wZ6RjORo=1q1_2GeqDBzqe8ChHOLrPv0pi+A@mail.gmail.com
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In response to Re: Processing long AND/OR lists  (Christopher Browne <cbbrowne@gmail.com>)
Responses Re: Processing long AND/OR lists  (Christopher Browne <cbbrowne@gmail.com>)
List pgsql-hackers
My last email was written before reading this. A few episodes of 24 occurred between writing and sending that email.

Added slony1-hackers, but didn't remove pgsql-hackers. Feel free to exclude pgsql lists, as this branch of conversation seems to be more Slony related than Postgres.

On Sun, May 26, 2013 at 10:59 PM, Christopher Browne <cbbrowne@gmail.com> wrote:

In Slony 2.1, the issue re-emerged because the ordering of the "action id" values was lost; the query had previously been implicitly forcing them into order; we had to add an "ORDER BY" clause, to make the "compressor" work again.
http://git.postgresql.org/gitweb/?p=slony1-engine.git;a=blobdiff;f=src/slon/remote_worker.c;h=b1f48043f8e25b4a74a392b0dbceeae8f3e18c27;hp=7fbf67c16f97cb7c3f209cf3be903ea52c4490a9;hb=c4ac435308a78a2db63bf267d401d842c169e87d;hpb=d4612aab78bac5a9836e3e2425c403878f7091c8


Commit log says it was fixed between  2.1.2, but from the Slony logs at the time, the version in use was 2.1.2. So
 
Joking about "640K" aside, it doesn't seem reasonable to expect a truly enormous query as is generated by the broken forms of this logic to turn out happily.  I'd rather fix Slony (as done in the above patch).

Yes, by all means, fix the application, but that doesn't preclude the argument that the database should be a bit more smarter and efficient, especially if it is easy to do.

Best regards,
--
Gurjeet Singh

http://gurjeet.singh.im/

EnterpriseDB Inc.

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