sql-optimization-patterns

Master SQL query optimization, indexing strategies, and EXPLAIN analysis to eliminate slow queries. Transform slow database queries into lightning-fast operations through systematic optimization, proper indexing, and query plan analysis. Understanding EXPLAIN output is fundamental to optimization. PostgreSQL EXPLAIN: Key Metrics to Watch: Indexes are the most powerful optimization tool. Index Types: Avoid SELECT *: Use WHERE Clause Efficiently: Optimize JOINs: Problem: N+1 Query Anti-Pattern Solution: Use JOINs or Batch Loading Bad: OFFSET on Large Tables Good: Cursor-Based Pagination Optimize COUNT Queries: Optimize GROUP BY: Transform Correlated Subqueries: Use CTEs for Clarity: Batch INSERT: Batch UPDATE: Pre-compute expensive queries. Split large tables for better performance. - Covers EXPLAIN plan analysis with key metrics (Seq Scan, Index Scan, cost, rows, execution time) and five index types (B-Tree, Hash, GIN, GiST, BRIN) for different query patterns - Includes five core optimization patterns: eliminating N+1 queries, cursor-based pagination, efficient aggregation, subquery transformation, and batch operations - Provides advanced techniques like materialized views, table partitioning, and query hints for large-scale performance tuning - Includes monitoring queries to identify slow queries, missing indexes, and unused indexes in PostgreSQL - Debugging slow-running...