Database Insights

PostgreSQL WAL retention is a balancing act — too little and standbys fall behind; too much and you risk disk exhaustion. Here's how to configure wal_keep_size and manage replication slots safely.

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

TiDB performs schema changes online without blocking reads or writes — using a distributed DDL queue across TiDB nodes. Here's how it works and how to monitor DDL jobs in production.

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.

MongoDB's Slot-Based Execution (SBE) engine introduced a plan cache memory leak affecting certain MongoDB versions — here's how to detect, mitigate, and fix it.

A critical bug in MongoDB 8.0 (SERVER-97368) affects TTL index behavior — causing documents to persist beyond expiration or delete prematurely. Here's how to detect and mitigate it.

AWS DMS can migrate terabytes of data with zero downtime — but default settings leave significant performance on the table. Here's how to tune DMS for production-grade migrations.

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.

In 2026, more database versions are hitting end-of-life than any year in recent history.

MySQL 8.4's audit log filter system lets you capture exactly the events your compliance framework requires — filtering by user, schema, event class, and severity to reduce audit log volume.

A practical guide to hardening PostgreSQL: configure SSL/TLS, tighten pg_hba.conf, implement least-privilege roles, enable row-level security, and set up audit logging.

PostgreSQL's logging system is powerful but requires careful configuration to be useful in production. Learn how to capture slow queries, connection events, and DDL changes without drowning in noise.