Partial Indexes and Expression Indexes in PostgreSQL: The Performance Wins Most Mobile Backend Developers Miss

--- title : " Partial Indexes in PostgreSQL: The Performance Wins Your Mobile Backend Misses" published : true description : " A hands-on tutorial on PostgreSQL partial indexes, expression indexes, and covering indexes — with real EXPLAIN ANALYZE benchmarks showing 57x query speedups for mobile API patterns." tags : postgresql, performance, api, architecture canonical_url : https://blog.mvpfactory.co/partial-indexes-postgresql-mobile-backend-performance --- ## What We Will Build By the end of this tutorial, you will know how to create partial indexes, expression indexes, and covering indexes in PostgreSQL that match the actual query patterns of a mobile backend. I will walk you through a real scenario — a notifications table with 50 million rows — and show you how to go from 47ms queries down to 0.4ms with targeted indexing. You will see every step with `EXPLAIN ANALYZE` output so nothing is hand-waved. ## Prerequisites - PostgreSQL 16 (11+ for `INCLUDE` syntax) - A table with a skewed