Re: partitioning materialized views

On Thu, Jul 6, 2017 at 11:25 AM, Shaun Thomas <shaun(dot)thomas(at)2ndquadrant(dot)com>
wrote:

> > I'm curious if I'm overlooking other possible architectures or tools
> that might make this simpler to manage.
>
> One of the issues with materialized views is that they are based on
> views... For a concurrent update, it essentially performs a looped
> merge, which can be pretty ugly. That's the price you pay to be
> non-blocking. For this particular setup, I'd actually recommend using
> something like pglogical to just maintain a live copy of the remote
> table or wait for Postgres 10's logical replication.

Unfortunately the foreign database is Hadoop. (As A Service)

> If you _can't_ do
> that due to cloud restrictions, you'd actually be better off doing an
> atomic swap.
>
> CREATE MATERIALIZED VIEW y AS ...;
>
> BEGIN;
> ALTER MATERIALIZED VIEW x RENAME TO x_old;
> ALTER MATERIALIZED VIEW y RENAME TO x;
> DROP MATERIALIZED VIEW x_old;
> COMMIT;
>
> This is an interesting idea. Thanks! I'll ponder that one.

> You could still follow your partitioned plan if you don't want to
> update all of the data at once. Let's face it, 3-4 hours is still a
> ton of data transfer and calculation.
>
>
yup.