Re: [HACKERS] advanced partition matching algorithm for partition-wise join

On 2018/06/26 18:02, Ashutosh Bapat wrote:
> On Tue, Jun 26, 2018 at 2:27 PM, Amit Langote
> <Langote_Amit_f8(at)lab(dot)ntt(dot)co(dot)jp> wrote:
>> Hi Ashutosh,
>>
>> On 2018/05/14 20:14, Ashutosh Bapat wrote:
>>> 0001-Hash-partition-bound-equality-refactoring.patch
>>> 0002-Targetlist-of-a-child-join-is-produced-by-translatin.patch
>>> 0003-Partition-wise-join-for-1-1-1-0-0-1-partition-matchi.patch
>>> 0004-Add-a-debug-message-to-notify-whether-partition-wise.patch
>>> 0005-Tests-for-0-1-1-1-and-1-0-partition-matching.patch
>>> 0006-Extra-extensive-tests-for-advanced-partition-matchin.patch
>>
>> I noticed after *cleanly* applying 0001-0004 to today's HEAD that while
>> 0005's test all pass, there are many failures in 0006's tests. Maybe, you
>> need to adjust something in one of the patches or adjust test outputs.
>
> If the failures are because of plan changes, it's expected. If those
> are because of crashes or changed output, those need to be fixed. I
> have kept that patch to notice any crashes or output changes, in which
> case, I pull that test into 0005 test set after fixing the code. Once
> we are near commit, I will remove that patch from the patchset.

Ah, okay. I thought of reporting this because I felt the errors may have
to do with changes to the related code in HEAD between May 14 when you
last posted the patches and today that you may need to account for in you
patches. For instance, there are many diffs like this:

***************
*** 90,132 ****
-- left outer join, with whole-row reference
EXPLAIN (COSTS OFF)
SELECT t1, t2 FROM prt1 t1 LEFT JOIN prt2 t2 ON t1.a = t2.b WHERE t1.b =
0 ORDER BY t1.a, t1.b, t1.c, t2.a, t2.b, t2.c;
! QUERY PLAN
! --------------------------------------------------------
Sort
Sort Key: t1.a, t1.c, t2.a, t2.b, t2.c
! -> Result
! -> Append
! -> Hash Right Join
! Hash Cond: (t2.b = t1.a)
! -> Seq Scan on prt2_p0 t2
! -> Hash
! -> Seq Scan on prt1_p0 t1
<snip>

--- 90,131 ----
-- left outer join, with whole-row reference
EXPLAIN (COSTS OFF)
SELECT t1, t2 FROM prt1 t1 LEFT JOIN prt2 t2 ON t1.a = t2.b WHERE t1.b =
0 ORDER BY t1.a, t1.b, t1.c, t2.a, t2.b, t2.c;
! QUERY PLAN
! --------------------------------------------------
Sort
Sort Key: t1.a, t1.c, t2.a, t2.b, t2.c
! -> Append
! -> Hash Right Join
! Hash Cond: (t2.b = t1.a)
! -> Seq Scan on prt2_p0 t2
! -> Hash
! -> Seq Scan on prt1_p0 t1
! Filter: (b = 0)

Looks like the Result node on top of Append is no longer there after
applying your patch.

Thanks,
Amit