Show the current database

SELECT currentDatabase()

Instead of PostgreSQL you can write into two databases

SELECT count() FROM db.table

Clickhouse has a variety of different datetime functions: https://clickhouse.tech/docs/ru/sql-reference/functions/date-time-functions/

Aggregations

Standard as avg / min / max / sum, and native to CH such as uniq(), quantile()

JOINS

• ANTI / SEMI JOINs are special to Clickhouse
• Super interesting feature: ASOF JOIN, to match approximate keys
• Sometimes it's useful to create dictionaries to store data in memory instead of JOINs

Creating Mat. Views