Mongodb

Cheatsheet: install, mongosh, databases, collections, CRUD.

Cheatsheet: embed vs reference, when to denormalize, anti-patterns.

Cheatsheet: aggregation stages, operators, performance.

Cheatsheet: index types, compound, sparse, TTL, text, geo.

Cheatsheet: array updates, findAndModify, bulk write.

Cheatsheet: PyMongo, motor async, mongoose, native node driver.

Cheatsheet: indexes, explain, profiling, slow ops.

Cheatsheet: replica set, oplog, failover, read preference.

Cheatsheet: sharding, shard key choice, balancer, jumbo chunks.

Cheatsheet: transactions, session, retry, limits.