plans for PostgreSQL 12

Hi

I am sending my ToDo for PostgreSQL 12 - a list of features what I would to
develop or I would to participate on:

1. schema variables - CREATE VARIABLE command
2. using pgbench expressions for psql - review, cooperation
3. JSON related patches - review
4. optimization expression without necessity to create snapshots -
experiments

@4 There are lot of not database expressions in PLpgSQL - like var1 := var1
+ var2 or var1 := var1 + konst. Own calculation needs about 1% of time of
total expression evaluation time. Almost all time get preparing plan cache,
preparing snapshot, .. For this case, when no database object is used, we
don't need use this infrastructure. I would to measure performance impact,
and testing if these optimizations are interesting or not.

I finalizing a article about PostgreSQL 11. It will great release. The
progress in partitioning area is massive. It is hard to believe so Postgres
has JIT. I hope so PostgreSQL will be better.

Regards

Pavel