Use postgres cstore_fdw instead of clickhouse

[ptman]

Prerequisites

• I have searched open and closed issues to make sure that the feature has not yet been requested.

Feature request

Is your feature request related to a problem? Please describe.
#301 clickhouse seems to be resource hungry and hard to administer for several users

How would you like it to work
Would postgres with cstore_fdw fill the same use case as clickhouse? Is it a viable alternative?