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

On Tue, Dec 5, 2017 at 11:04 AM, Rajkumar Raghuwanshi
<rajkumar.raghuwanshi@enterprisedb.com> wrote:
> On Mon, Dec 4, 2017 at 7:34 AM, Ashutosh Bapat
> <ashutosh.bapat@enterprisedb.com> wrote:
>> I agree, the patch looks longer than expected. I think, it's important
>> to have some testcases to test partition-wise join with default
>> partitions. I think we need at least one test for range default
>> partitions, one test for list partitioning, one for multi-level
>> partitioning and one negative testcase with default partition missing
>> from one side of join.
>>
>> May be we could reduce the number of SQL commands and queries in the
>> patch by adding default partition to every table that participates in
>> partition-wise join (leave the tables participating in negative tests
>> aside.). But that's going to increase the size of EXPLAIN outputs and
>> query results. The negative test may simply drop the default partition
>> from one of the tables.
>>
>> For every table being tested, the patch adds two ALTER TABLE commands,
>> one for detaching an existing partition and then attach the same as
>> default partition. Alternative to that is just add a new default
>> partition without detaching and existing partition. But then the
>> default partition needs to populated with some data, which requires 1
>> INSERT statement at least. That doesn't reduce the size of patch, but
>> increases the output of query and EXPLAIN plan.
>>
>> May be in case of multi-level partitioning test, we don't need to add
>> DEFAULT in every partitioned relation; adding to one of them would be
>> enough. May be add it to the parent, but that too can be avoided. That
>> would reduce the size of patch a bit.
>
> Thanks Ashutosh for suggestions.
>
> I have reduced test cases as suggested. Attaching updated patch.
>
Sorry Attached wrong patch.

attaching correct patch now.