Horton

Re: Partition-wise join for join between (declaratively) partitioned tables

Robert Haas <robertmhaas@gmail.com>

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From: Robert Haas <robertmhaas@gmail.com>
To: Ashutosh Bapat <ashutosh.bapat@enterprisedb.com>
Cc: Rajkumar Raghuwanshi <rajkumar.raghuwanshi@enterprisedb.com>, pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2017-03-20T16:29:32Z
Lists: pgsql-hackers 
On Mon, Mar 20, 2017 at 9:44 AM, Ashutosh Bapat
<ashutosh.bapat@enterprisedb.com> wrote:
> Right. If we could use parent Vars to indicate parent Var or child Var
> depending upon the context, a lot of memory issues would be solved; we
> wouldn't need to translate a single expression. But I think that's not
> straight forward. I have been thinking about some kind of polymorphic
> Var node, but it seems a lot more invasive change. Although, if we
> could get something like that, we would save a huge memory. :)

Yes, that's why I'm interested in exploring that approach once the
basic framework is in place here.

> I am wondering whether we need to change
> calc_non_nestloop_required_outer() similar to
> calc_nestloop_required_outer() just to keep their signatures in sync.

I haven't looked at the patch, but I don't think you need to worry about that.

> Should I work on completing reparamterized_path_by_child() to support
> all kinds of paths?

Yes, or at the very least all scans, like reparameterize_path() already does.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company

Commits

  1. Basic partition-wise join functionality.

  2. Assorted preparatory refactoring for partition-wise join.

  3. Teach adjust_appendrel_attrs(_multilevel) to do multiple translations.

  4. Stamp 10beta2.

  5. Eat XIDs more efficiently in recovery TAP test.

  6. Abstract logic to allow for multiple kinds of child rels.

  7. Implement SortSupport for macaddr data type

  8. Attempt to stabilize grouping sets regression test plans.

  9. Teach xlogreader to follow timeline switches

  10. Don't scan partitioned tables.

  11. Fix grammar.

  12. postgres_fdw: Push down FULL JOINs with restriction clauses.

  13. Some preliminary refactoring towards partitionwise join.

  14. contrib/amcheck needs RecentGlobalXmin to be PGDLLIMPORT'ified.

  15. Print test parameters like "foo: 123", and results like "foo = 123".