Module 01 · 3 lessons
Engine and transaction boundaries
Locate durable order state across storage engines, MVCC, logs, and local transaction outcomes.
16 reading lessons · 1 deterministic capstone
Protect the durable order, not just the database process.
Follow one Spring order service from storage and transactions through concurrency, capacity, migration, replication, restore, scale, and verified incident recovery.
Six ordered modules · dual-engine baseline
Move from local correctness to recovery evidence.
Shared relational concepts stay separate from PostgreSQL 18 and MySQL 8.4 InnoDB mechanisms.
Module 02 · 3 lessons
Concurrency and application correctness
Protect order invariants with explicit isolation, deadlock, and optimistic-conflict decisions.
Module 03 · 3 lessons
Query and connection capacity
Connect indexes, plans, statistics, transactions, and finite connection ownership.
Module 04 · 4 lessons
Change, replication, and recovery
Ship compatible change, reason about replicas and failover, and prove recoverability through restore evidence.
Module 05 · 3 lessons
Scale and incident operations
Measure before sharding, preserve safe engine evidence, mitigate reversibly, and verify business recovery.
Module 06 · Capstone lab
Capstone lab
Model pool saturation, lock waits, retry amplification, replica lag, and failover ambiguity without contacting a database.
Browser-only capstone
Model contention, then request the engine evidence the model cannot provide.
The lab is not a benchmark, capacity calculator, database dry-run, failover exercise, RPO/RTO calculator, or production verification.
Course library
Review all readings and the capstone guide.
Upgraded lessons keep their canonical slugs and browser-local progress keys.
System Design Aug 19, 2026 3 min read
Production Database Engineering Systems Explained
Trace one Spring order service across relational, engine, transaction, capacity, replication, backup, and recovery boundaries.
Databases Aug 19, 2026 3 min read
PostgreSQL and MySQL Storage Engines and MVCC Explained
Compare PostgreSQL tuple visibility and vacuum with MySQL 8.4 InnoDB undo and purge without inventing one shared engine model.
System Design Jun 29, 2026 5 min read
Database Transactions Explained
Learn what database transactions are, why ACID matters, how commits and rollbacks work, and what backend developers should know.
System Design Jul 25, 2026 9 min read
Database Isolation Levels Explained
Compare database isolation levels, concurrency anomalies, PostgreSQL and MySQL behavior, and safe Spring and Node.js transaction patterns.
System Design Jul 25, 2026 9 min read
Database Deadlocks Explained
Learn why database deadlocks happen, how PostgreSQL and MySQL detect them, and how to prevent and retry them safely in Java and Node.js.
System Design Jun 28, 2026 5 min read
Optimistic Locking Explained
Learn how optimistic locking prevents lost updates in backend systems using version columns, compare-and-swap updates, and 409 conflicts.
System Design Jun 28, 2026 5 min read
Database Indexes Explained
Learn how database indexes work, why they speed up reads, when they slow down writes, and how backend developers should choose indexes.
System Design Jul 1, 2026 8 min read
Database Connection Pooling Explained
Learn database connection pooling for backend systems, including pool size, timeouts, leaks, max connections, queues, monitoring, and common mistakes.
Databases Aug 19, 2026 3 min read
PostgreSQL and MySQL Query Plans and Statistics Explained
Interpret estimates, runtime plans, statistics, parameters, and index choices using each engine's documented evidence boundaries.
System Design Jul 1, 2026 7 min read
Database Migration Rollback Explained
Learn database migration rollback strategies, including backward-compatible changes, expand-contract migrations, backups, deploy order, and recovery plans.
System Design Jul 25, 2026 9 min read
Database Read Replicas Explained
Learn how database read replicas work, where replica lag breaks correctness, and how to route reads safely in Spring and Node.js services.
System Design Jul 25, 2026 9 min read
Database Backup and Restore Explained
Design database backups around RPO and RTO, compare logical, physical, snapshot, and PITR methods, and build restore drills that prove recovery.
System Design Aug 19, 2026 3 min read
PostgreSQL and MySQL Replication and Failover Explained
Separate replication, apply, promotion, fencing, client routing, consistency, and ambiguous write evidence across both engines.
System Design Jun 29, 2026 6 min read
Database Sharding Explained
Learn what database sharding is, when backend systems need it, how shard keys work, and what tradeoffs sharding creates.
Observability Aug 19, 2026 3 min read
PostgreSQL and MySQL Observability and Capacity Explained
Correlate demand, pools, sessions, transactions, locks, plans, storage, logs, and replicas without leaking sensitive database data.
Operations Aug 19, 2026 3 min read
Production Database Incident Troubleshooting
Diagnose pool exhaustion, lock contention, slow plans, failed migrations, replica lag, storage pressure, and failover ambiguity.
Reliability Labs Aug 19, 2026 3 min read
Database Connection Contention and Recovery Lab Examples
Use six deterministic browser scenarios to reason about pools, locks, retries, replica lag, failover interruption, and evidence boundaries.
FAQ
Production Database course questions
Does this course connect to a database?
No. SQL and commands are explanatory text, and the capstone is a deterministic browser-only model with no database, network, credential, storage, or telemetry access.
Are PostgreSQL and MySQL behaviors interchangeable?
No. Every lesson separates the shared relational contract from PostgreSQL 18 and MySQL 8.4 InnoDB mechanisms and evidence.
Does a successful backup job prove recovery?
No. Recoverability requires an isolated restore using the documented log chain plus schema, constraint, application, and durable business-state verification.
Can the capstone size a production pool?
No. Its steps and request counts are teaching units, not measurements, benchmarks, forecasts, RPO, RTO, or production advice.