Native Postgres Handler in databend

[sundy-li]

Postgresql is a very popular database, Vote +1/-1 If you like to have pg protocol support in databend.

https://github.com/sunng87/pgwire could be a good crate option.

[flaneur2020]

I'd sugguest write a standalone proxy middleware in another repository over databend's flight API:

• the flight protocol is easier to integrate with cloud native infrastructure like services in Kubernetes, easy to load balance and offering services to users. (on the oppose side, it's hard to expose an Postgres port to customers in kubernetes
• the pg-over-flight middleware can be used in other projects, and we can get contributions from whom use it.
• we can also deploy the middleware as a sidecar aside with databend, which offers the benefits of the postgres protocol, but simplifies the maintence work about databend's protocols (there have already too many protocols, makes it harder for users to choose the best maintained one).

[sundy-li]

Agree， we should maintain a main protocol.

[sundy-li]

But it needs another service to deploy.

[flaneur2020]

IMHO, deploying a sidecar is cheap in kuberenetes.

In the virtual machine deployments, a gateway like PG proxy is also not hard to deploy at all. It's totally stateless, can be started up with a plain backend list config.