SQL & Relational Databases Production-grade SQL skills for designing, querying, and optimizing relational databases in data engineering workflows. Quick Start Core Concepts 1. Query Optimization with EXPLAIN ANALYZE 2. Indexing Strategies 3. Window Functions (2024-2025 Essential) 4. Transaction Isolation & ACID 5. Partitioning for Scale Tools & Technologies | Tool | Purpose | Version (2025) | |------|---------|----------------| | PostgreSQL | Primary OLTP database | 16+ | | MySQL | Alternative OLTP | 8.0+ | | DBeaver | Universal SQL client | Latest | | pgAdmin | PostgreSQL admin | 8+ | | pgcl…