On Thu, Oct 10, 2019 at 3:09 PM Lev Kokotov <lev.kokotov@xxxxxxxxx> wrote:
Hi Miles,One issue is keeping the subscriber and the publisher schema identical. Running migrations on both the publisher and subscriber does not seem atomic to me, therefore I don't have a way to enforce consistency between the two. The use case is simple: schemas change all the time, and keeping two databases (or more!) in sync manually is tough.
We had this requirement as well and this is why I wrote pgl_ddl_deploy on top of pglogical to handle the issue. It's by no means an all-encompassing solution, but it's worked really well for us. It only supports pglogical currently (which could be expanded for in-core logical... but we have not tried yet).
It basically uses event triggers, and inspecting what is being executed, as an idea of how to propagate DDL.
However, I am very interested in future of this feature for in-core logical replication in a much more natively-supported way. As such, I have not heard anything for awhile. Schema mapping for logical replication is another feature we really would want, and would also very much relate to DDL replication. @Alvaro Herrera did a lot of great work on support for in-core DDL replication a few years back. Here is that thread: https://postgr.es/m/CACACo5QQuAV+n4Gi+YA1JF_a+QenR6SJuP8CYdPSrXKa+FHS3A@xxxxxxxxxxxxxx
Thanks,
Jeremy
Jeremy
