Performance

0001-01-01

Reading EXPLAIN

EXPLAIN reveals the plan PostgreSQL chose without running the query. Reading cost, row estimates, and node type fluently is the starting point for all query analysis.

0001-01-01

An Indexing Strategy

Indexes follow from your queries, not your tables. An index is a named trade: faster reads in exchange for slower writes. Only make trades you can justify.

0001-01-01

Query Rewriting and Anti-Patterns

Small SQL changes can have large performance effects. The most common slow queries share a recognizable EXPLAIN signature and a mechanical fix.

0001-01-01

The FILTER Clause: Multiple Counts in One Pass

count(*) FILTER (WHERE condition) computes conditional aggregates without CASE expressions or separate subqueries — one scan, multiple results.