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2026-04-21 17:30
Indexing Strategies for Faster Database Queries
TL;DR
Indexes = direct lookups — milliseconds vs full table scans (seconds).
B-tree for most queries — Supports =, <, >, BETWEEN, LIKE 'prefix%', ORDER BY.
Index WHERE / JOIN / ORDER BY columns — Otherwise full scan.
Composite index order matters — (a, b, c) works for a, a+b, a+b+c — not b or c alone. Equality first, then range.
Partial indexes — WHERE active = true = smalle...
