12 — SQL & Databases¶
SQL, relational databases, and NoSQL systems.
Scope¶
Cheat sheets for querying and administering databases. Distributed processing belongs to 13-Big-Data.
Cheat Sheets¶
| Cheat Sheet | Description |
|---|---|
| sql.md | The complete SQL reference: SELECT/WHERE/GROUP BY/HAVING, all JOINs, UNION, subqueries, CTEs, window functions, DDL/DML, keys, indexes, views, transactions, NULL, dates, strings |
| postgresql.md | PostgreSQL: psql, types, JSONB, full-text search, arrays, EXPLAIN, COPY, upserts, performance |
| mysql.md | MySQL/MariaDB: dialect notes, date/string functions, indexing, EXPLAIN, users & grants |
| sqlite.md | Embedded SQLite: Python sqlite3 + pandas round-trips, pragmas, local-data caching |
| mongodb.md | MongoDB: documents, CRUD, aggregation pipelines, $lookup, indexes, pandas interop |
| redis.md | Redis: caching, TTL, rate limiting, queues, sorted sets, pub/sub, feature-cache patterns |
Planned Cheat Sheets¶
- DuckDB — in-process analytical SQL for data science
Contribute¶
- Template: CHEATSHEET_TEMPLATE.md
- Guide: CONTRIBUTING.md