📄️ SQL Quick Reference
Copy-paste SQL reference — clause order, operators, functions, joins, window frames, DDL, types, dialect differences (PostgreSQL, MySQL, SQLite, SQL Server), CLI commands, and handy queries.
📄️ SQL Best Practices
Habits that make SQL easier to read, faster, and safe to run — formatting, naming, NULLs, joins, index-friendly filters, safe changes, schema design, migrations, security, testing, and a pre-merge checklist.