Horton

Re: Declarative partitioning - another take

Amit Langote <langote_amit_f8@lab.ntt.co.jp>

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From: Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>
To: Ashutosh Bapat <ashutosh.bapat@enterprisedb.com>
Cc: Alvaro Herrera <alvherre@2ndquadrant.com>, Robert Haas <robertmhaas@gmail.com>, Amit Langote <amitlangote09@gmail.com>, Rajkumar Raghuwanshi <rajkumar.raghuwanshi@enterprisedb.com>, Pg Hackers <pgsql-hackers@postgresql.org>
Date: 2016-11-25T09:16:51Z
Lists: pgsql-hackers 
On 2016/11/25 13:51, Ashutosh Bapat wrote:
>>
>> I assume you meant "...right after the column name"?
>>
>> I will modify the grammar to allow that way then, so that the following
>> will work:
>>
>> create table p1 partition of p (
>>      a primary key
>> ) for values in (1);
>>
> 
> That seems to be non-intuitive as well. The way it's written it looks
> like "a primary key" is associated with p rather than p1.

It kind of does, but it's still a "create table p1" statement, so it's not
that ambiguous, IMHO.  Although I'm not attached to this syntax, there may
not be other options, such as moving the parenthesized list right before
"partition of", due to resulting grammar conflicts.

> Is there any column constraint that can not be a table constraint?

NOT NULL, DEFAULT, and COLLATE (although only the first of these is really
a constraint, albeit without a pg_constraint entry)

> If no, then we can think of dropping column constraint syntax all
> together and let the user specify column constraints through table
> constraint syntax. OR we may drop constraints all-together from the
> "CREATE TABLE .. PARTITION OF" syntax and let user handle it through
> ALTER TABLE commands. In a later version, we will introduce constraint
> syntax in that DDL.

Hmm, it was like that in the past versions of the patch, but I thought
it'd be better to follow the CREATE TABLE OF style to allow specifying the
table and column constraints during table creation time.  If many think
that it is not required (or should have some other syntax), I will modify
the patch accordingly.

Thanks,
Amit

Commits

  1. Fix typo.

  2. Document trigger-firing behavior for inheritance/partitioning.

  3. Fire per-statement triggers on partitioned tables.

  4. Set ecxt_scantuple correctly for tuple routing.

  5. Fix interaction of partitioned tables with BulkInsertState.

  6. Avoid core dump for empty prepared statement in an aborted transaction.

  7. Fix some problems in check_new_partition_bound().

  8. Remove unnecessary arguments from partitioning functions.

  9. Fix reporting of constraint violations for table partitioning.

  10. Fix tuple routing in cases where tuple descriptors don't match.

  11. Invalid parent's relcache after CREATE TABLE .. PARTITION OF.

  12. Doc: improve documentation about inheritance.