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Databases guide

Databases, Deeply

A deep, plain-English guide to how relational databases actually work — the relational model, indexes and B-trees, joins and query planning, transactions and ACID, isolation levels and locking, normalization, SQL vs NoSQL, and the connection pool and N+1 problems at the application seam. No hype.

8 lessons·≈ 1 hr read·Free, no account
  1. 01Tables, Rows & Schemas: The Relational ModelBeginner·9 min
  2. 02How Indexes Work: Inside the B-TreeIntermediate·10 min
  3. 03Joins & Query Planning: How SQL Actually RunsIntermediate·10 min
  4. 04Transactions & ACID: The Correctness GuaranteeIntermediate·9 min
  5. 05Isolation Levels & Locking: Concurrency Without ChaosAdvanced·11 min
  6. 06Normalization vs Denormalization: Shaping Data WellIntermediate·9 min
  7. 07SQL vs NoSQL: When Each Actually WinsIntermediate·10 min
  8. 08Connection Pools & the N+1 ProblemIntermediate·9 min