SQL Best Practices

Query Writing

• Use parameterized queries (prevent SQL injection)
• Select only needed columns (avoid SELECT *)
• Use appropriate JOINs
• Add WHERE clauses to limit results
• Use EXPLAIN to analyze queries

Indexing

• Index columns used in WHERE/JOIN/ORDER BY
• Use composite indexes for multi-column queries
• Don't over-index (slows writes)
• Consider covering indexes
• Monitor index usage