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Query Rewriting Patterns: Overview

Module: Query Optimization & Performance

Transform slow queries into faster equivalents using proven rewriting patterns

Convert OR conditions to UNION ALL for index usage (10-100x speedup)

Rewrite subqueries as JOINs to eliminate nested loops

Replace NOT IN with LEFT JOIN for NULL-safe performance

Use EXISTS instead of IN for large datasets

Apply window functions instead of correlated subqueries

Transform slow queries into faster equivalents using proven rewriting patterns

Convert OR conditions to UNION ALL for index usage (10-100x speedup)

Rewrite subqueries as JOINs to eliminate nested loops

Replace NOT IN with LEFT JOIN for NULL-safe performance

Use EXISTS instead of IN for large datasets

Apply window functions instead of correlated subqueries