data-analyst-sql-optimization

Apply SQL optimization patterns including index usage, query rewriting, JOIN optimization, and window functions. Use when improving query performance or analyzing slow queries. This skill provides comprehensive SQL optimization patterns and best practices: - N+1 query elimination - Index optimization strategies - JOIN vs subquery performance - Window functions for complex aggregations - Query execution plan analysis Triggers: "optimize SQL", "slow query", "improve performance", "SQL最適化", "クエリ改善", "パフォーマンス向上"