pg_clickhouse v0.10: Subquery pushdown and 1000x faster TPC-H queries

56 pointsposted 10 hours ago
by saisrirampur

5 Comments

nasretdinov

21 minutes ago

As someone who tried doing things like condition pushdown, transpiling from one language to another, etc, this is really impressive. Correctly pushing subqueries while preserving the semantics of the original database is something I can't imagine I could've ever achieved

manbash

8 hours ago

> December's headline feature was teaching the planner to push a whole correlated EXISTS subquery down as a single LEFT SEMI JOIN instead of a nested loop with one ClickHouse round trip per outer row. This moved the needle from 3 of 22 TPC-H queries all the way to 12.

LLMs sure love throwing in archaic expressions such as "move the needle". The abrupt contrast in jargons is so unpleasant and keeps throwing me off right in the middle of reading.

hi_hi

3 hours ago

LLMs have provided the uncanny valley to writing.