PG Phriday: Joining the Big Leagues
I’ve maintained since about 2011, that the problem with scaling Postgres to truly immense installations could be solved by a query coordinator. Why? Most sharding systems utilize an application-level distribution mechanism, which may or may not leverage an inherent hashing algorithm. This means each Postgres instance can be treated independently of all the others if the distribution process is known. On a cleverly architected system, the application is algorithm aware, and can address individual shards through a driver proxy or accessor class.