From: | Robert Haas <robertmhaas(at)gmail(dot)com> |
---|---|
To: | Amit Khandekar <amitdkhan(dot)pg(at)gmail(dot)com> |
Cc: | Dilip Kumar <dilipbalaut(at)gmail(dot)com>, Amit Kapila <amit(dot)kapila16(at)gmail(dot)com>, Amit Langote <Langote_Amit_f8(at)lab(dot)ntt(dot)co(dot)jp>, Etsuro Fujita <fujita(dot)etsuro(at)lab(dot)ntt(dot)co(dot)jp>, pgsql-hackers <pgsql-hackers(at)postgresql(dot)org>, Ashutosh Bapat <ashutosh(dot)bapat(at)enterprisedb(dot)com> |
Subject: | Re: UPDATE of partition key |
Date: | 2017-10-03 19:38:00 |
Message-ID: | CA+TgmoZLaWgbqRsQjPZ6ty3BJjqjOJeD59gF66NSxsY12dPY9A@mail.gmail.com |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-hackers |
On Tue, Oct 3, 2017 at 8:16 AM, Amit Khandekar <amitdkhan(dot)pg(at)gmail(dot)com> wrote:
> While writing this down, I observed that after multi-level partition
> tree expansion was introduced, the child table expressions are not
> converted directly from the root. Instead, they are converted from
> their immediate parent. So there is a chain of conversions : to leaf
> from its parent, to that parent from its parent, and so on from the
> root. Effectively, during the first conversion, there are that many
> ConvertRowtypeExpr nodes one above the other already present in the
> UPDATE result rel expressions. But my patch handles the optimization
> only for the leaf partition conversions.
>
> If already has CRE : CRE(rr) -> wr(r)
> Parent-to-child conversion ::: CRE(p) -> wr(r) ===> CRE(rr) ->
> CRE(r) -> wr(c1)
> W patch : CRE(rr) -> CRE(r) -> wr(c1) ===> CRE(rr) -> CRE(r) -> wr(c2)
Maybe adjust_appendrel_attrs() should have a similar provision for
avoiding extra ConvertRowTypeExpr nodes?
--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company
From | Date | Subject | |
---|---|---|---|
Next Message | Nico Williams | 2017-10-03 19:51:30 | [PATCH] WIP Add ALWAYS DEFERRED option for constraints |
Previous Message | Robert Haas | 2017-10-03 19:27:14 | Re: Partition-wise join for join between (declaratively) partitioned tables |