Re: [HACKERS] Logical Replication WIP

On 17/12/16 13:37, Erik Rijkers wrote:
> On 2016-12-16 13:49, Petr Jelinek wrote:
>>
>> version 13 of the patch.
>>
>> 0001-Add-PUBLICATION-catalogs-and-DDL-v13.patch.gz (~32 KB)
>> 0002-Add-SUBSCRIPTION-catalog-and-DDL-v13.patch.gz (~28 KB)
>> 0003-Define-logical-rep...utput-plugi-v13.patch.gz (~13 KB)
>> 0004-Add-logical-replication-workers-v13.patch.gz (~44 KB)
>> 0005-Add-separate-synch...or-logical--v13.patch.gz (~2 KB)
> 
> Hi,
> 
> You wrote on 2016-08-05: :
> 
>> What's missing:
>>  - sequences, I'd like to have them in 10.0 but I don't have good
>>    way to implement it. PGLogical uses periodical syncing with some
>>    buffer value but that's suboptimal. I would like to decode them
>>    but that has proven to be complicated due to their sometimes
>>    transactional sometimes nontransactional nature, so I probably
>>    won't have time to do it within 10.0 by myself.
> 
> I ran into problems with sequences and I wonder if sequences-problems
> are still expected, as the above seems to imply.
> 
> (short story: I tried to run pgbench across logical replication; and
> therefore
> added a sequence to pgbench_history to give it a replica identity, and
> cannot get it to work reliably ).
> 

Sequences are not replicated but that should not prevent pgbench_history
itself from being replicated when you add serial to it.

BTW you don't need to add primary key to pgbench_history. Simply ALTER
TABLE pgbench_history REPLICA IDENTITY FULL; should be enough.

--  Petr Jelinek                  http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training &
Services