The JusDB Database Engineering Blog

Set up MySQL Orchestrator for automatic failover, topology discovery, and master election at scale

Use MySQL Performance Schema to profile queries, monitor memory, and diagnose bottlenecks without guesswork

2025 was the year databases competed on operational simplicity. Serverless databases matured, pgvector merged vector search into PostgreSQL, and CDC became standard infrastructure. Here's what mattered and what's next.

Five counterintuitive database performance truths every engineer gets wrong — over-indexing costs, N+1 queries, connection pool sizing, replica reads, and EXPLAIN limitations.

RDS MySQL audit logs stored in CloudWatch cost significantly more than S3 — and most teams don't need real-time log access. Here's how to export audit logs to S3 and cut your AWS bill.

Understand when MySQL JSON columns help and hurt performance. Learn functional indexes, JSON_TABLE, and when to migrate JSON to normalized columns.

Teams take down production for hours with migrations that could be zero-downtime operations. Learn to use gh-ost and CREATE INDEX CONCURRENTLY, implement rollback plans, and apply the expand-contract pattern for breaking changes.

MySQL's foreign key implementation has evolved significantly from 5.7 through 8.4 — with changes to metadata locking, instant DDL interactions, and Group Replication behavior that every DBA needs to understand.

Master InnoDB buffer pool internals: page management, chunk allocation, LRU algorithm, and tuning strategies for maximum cache efficiency.

Use MySQL 8.0 generated columns to index computed values, JSON paths, and date parts. Covers virtual vs stored tradeoffs and functional index patterns.

Debezium 3.0 turns your database transaction log into a real-time event stream with full before/after row images. Learn to configure CDC for PostgreSQL WAL and MySQL binlog, avoid the offset storage trap, and monitor replication lag.

Guide MySQL query execution with optimizer hints. Covers INDEX, NO_INDEX, JOIN_ORDER, MAX_EXECUTION_TIME, and query block naming for subquery hint targeting.