By the way I can see there are some already but I do not use them https://github.com/Infinidat/infi.clickhouse_fdw/ https://github.com/adjust/clickhouse_fdw
It would be beneficial to couple transactional data (Postgres) with OLAP data (CH). There are a few other things coming in PG which might mitigate the need for CH too (pluggable storage, zheap), so we're not going to rush this part.
By the way I can see there are some already but I do not use them https://github.com/Infinidat/infi.clickhouse_fdw/ https://github.com/adjust/clickhouse_fdw