Hello! I'm kicking off another article series about the internals of PostgreSQL. This one will focus on query planning and execution mechanics. This series will cover: Query execution stages (this article) Statistics Sequential scan Index scan Nested-loop join Hash join Merge join This article borrows from our course QPT Query Optimization (available in English soon), but focuses mostly on the int
![Queries in PostgreSQL. Query execution stages](https://cdn-ak-scissors.b.st-hatena.com/image/square/f2a1cf0568128c6f662b7eff922dd0679cafe126/height=288;version=1;width=512/https%3A%2F%2Fhabrastorage.org%2Fgetpro%2Fhabr%2Fupload_files%2Ff5d%2F37b%2F340%2Ff5d37b340ded248e1545b3e7cc88702f.png)