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.
Tag
Databases
23 articles with this tag. Follow these related notes when you want a narrower study path.
Backend Aug 5, 2026 11 min read
Spring Data JPA Query Performance Explained
Diagnose Spring Data JPA performance with query, SQL, plan, row, pool-wait, and user-latency evidence instead of relying on fetch-strategy folklore.
Backend Aug 5, 2026 11 min read
Spring Boot Integration Testing with Testcontainers Explained
Use Spring test slices, full-context contracts, Testcontainers PostgreSQL, migrations, security, and failure injection without overstating production equivalence.
System Design Aug 4, 2026 10 min read
Composite, Covering, and Partial Indexes Explained
Learn to design composite, covering, and partial PostgreSQL indexes from real query predicates, ordering, projections, selectivity, and write-cost evidence.
System Design Aug 4, 2026 11 min read
Database Lock Contention and Long Transactions Explained
Learn to diagnose PostgreSQL lock contention, blockers, waiters, long transactions, idle-in-transaction sessions, pool exhaustion, and safe cancellation.
System Design Aug 4, 2026 11 min read
Database Query Performance for Backend Systems Explained
Learn how to diagnose database query performance using user impact, execution plans, planner estimates, I/O, locks, MVCC, connection pools, and safe production validation.
System Design Aug 4, 2026 10 min read
MVCC, VACUUM, and Table Bloat Explained
Learn how PostgreSQL MVCC, snapshots, dead tuples, autovacuum, visibility maps, freezing, HOT updates, and table or index bloat affect backend performance.
System Design Aug 4, 2026 10 min read
PostgreSQL EXPLAIN and Query Plans Explained
Learn to read PostgreSQL EXPLAIN plans safely, including costs, estimated and actual rows, loops, scans, joins, sorts, buffers, WAL, and production boundaries.
System Design Aug 4, 2026 10 min read
Production Slow Query Troubleshooting for Backend Systems
Use a production runbook to connect user impact, query fingerprints, waits, plans, estimates, buffers, locks, MVCC, pools, mitigations, and verified recovery.
System Design Aug 4, 2026 10 min read
Query Planner Statistics and Cardinality Estimation Explained
Learn how query planners estimate rows using statistics, selectivity, histograms, most-common values, correlation, extended statistics, and production validation.
System Design Aug 4, 2026 10 min read
Table Partitioning and Partition Pruning Explained
Learn PostgreSQL table partitioning, partition keys, pruning, lifecycle maintenance, indexes, constraints, prepared queries, and production validation.
System Design Aug 4, 2026 11 min read
Zero-Downtime Database Schema Migrations Explained
Learn expand-contract database migrations, compatible deploy ordering, bounded backfills, concurrent indexes, constraint validation, locking, and safe production rollout.
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 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 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 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 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.
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 1, 2026 6 min read
N+1 Query Problem Explained
Learn the N+1 query problem in backend apps, including ORM loading, SQL examples, eager loading, batching, joins, query counts, and fixes.
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.
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 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 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.