https://www.compilemymind.com/tags/database-performance/ Recent content in Database-Performance on Compile My Mind Hugo en Sun, 26 Jul 2026 18:40:00 +0200 https://www.compilemymind.com/posts/postgresql-indexes-types-tradeoffs-query-verification/ Mon, 20 Jul 2026 17:34:55 +0300 https://www.compilemymind.com/posts/postgresql-indexes-types-tradeoffs-query-verification/ <p>“Add an index” is incomplete advice. A useful PostgreSQL index must match:</p> <ul> <li>the operators in a real query;</li> <li>the order and selectivity of its predicates;</li> <li>any required ordering;</li> <li>the distribution and physical layout of production-like data; and</li> <li>the write, storage, and maintenance budget.</li> </ul> <p>The planner is free to ignore an index when a sequential scan is cheaper. Your goal is not to force an index icon into <code>EXPLAIN</code>; it is to reduce total workload cost.</p>