Re: [GENERAL] Logical replication

On 04/30/2017 09:07 AM, Adrian Klaver wrote:
> I have started looking at the logical replication feature in Postgres
> 10. One thing I have no been able to determine is the interoperability
> between it and pglogical(www.2ndquadrant.com/en/resources/pglogical/). I
> know the one is derived from the other, what I can not find is whether a
> Postgres 9.4 instance with the pglogical extension installed can
> communicate with a Postgres 10 instance using the built in code?
>

Some testing says the answer is no:

postgres=# CREATE SUBSCRIPTION pgsql10sub CONNECTION
'dbname=replication_test host=localhost user=postgres port=5412'
PUBLICATION pgsql94;
ERROR:  could not receive list of replicated tables from the publisher:
ERROR:  syntax error

If I am correct, this means from 9.4 <--> 10 and points in between you
would need to use the pglogical extension on both ends. Going from 10
--> you could use the builtin logical replication. This leads to another
question. Is is possible to use both at the same time?:

9.4       --->   10(instance 1)    ---> 10(instance 2)
pglogical        pglogical
                  builtin                builtin

--
Adrian Klaver
adrian.klaver@aklaver.com