Horton

Re: pgsql: Support partition pruning at execution time

David Rowley <david.rowley@2ndquadrant.com>

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From: David Rowley <david.rowley@2ndquadrant.com>
To: Andrew Gierth <andrew@tao11.riddles.org.uk>
Cc: Alvaro Herrera <alvherre@alvh.no-ip.org>, Tom Lane <tgl@sss.pgh.pa.us>, pgsql-committers@lists.postgresql.org
Date: 2018-04-08T03:25:32Z
Lists: pgsql-hackers 
On 8 April 2018 at 15:21, Andrew Gierth <andrew@tao11.riddles.org.uk> wrote:
>  David> Setting autovacuum_naptime to 10 seconds makes it occur in 10
>  David> second intervals...
>
> Analyze (including auto-analyze on a different table entirely) has a
> snapshot, which can hold back OldestXmin, hence preventing the
> all-visible flag from being set.

urg, that's true.

Seems like there's no bugs here then;

begin work;
set transaction isolation level repeatable read;
select * from pg_class;
-- do nothing

makes the script go crazy.

You're right, thanks.

I guess the patch I sent is the way forward with this.


-- 
 David Rowley                   http://www.2ndQuadrant.com/
 PostgreSQL Development, 24x7 Support, Training & Services

Commits

  1. Update Append's idea of first_partial_plan

  2. Fix IndexOnlyScan counter for heap fetches in parallel mode

  3. Fix incorrect logic for choosing the next Parallel Append subplan

  4. Minor comment updates

  5. Attempt to stabilize partition_prune test output.

  6. Support partition pruning at execution time