Database Insights

Essential MySQL diagnostic queries every DBA needs. Quickly identify slow queries, lock contention, replication lag, memory issues, and connection problems.

MySQL replication filters let you replicate only specific databases or tables — but misconfiguration can silently drop transactions. Here's how to use binlog-do-db, replicate-do-db, and replicate-do-table safely.

Understand MySQL max_connections, thread caching, and connection pool sizing to handle high-concurrency workloads

A comprehensive guide to MySQL replication lag — why it happens, why Seconds_Behind_Master lies, how to measure accurately with pt-heartbeat, and how to fix it with multi-threaded replication and LOGICAL_CLOCK parallelism.

Deploy PMM to get deep MySQL and PostgreSQL visibility — query analytics, dashboards, and alerting in one tool

MySQL's EXPLAIN command reveals exactly how the query optimizer plans to execute your SQL — which indexes it will use, how many rows it expects to examine, and where it may sort or create temporary tables.

A production guide to online MySQL schema changes — when to use pt-online-schema-change vs gh-ost vs MySQL 8.0 INSTANT DDL, configuration parameters, the cutover mechanism, and a step-by-step safety playbook.

GTIDs eliminate manual binlog position tracking in MySQL replication. This guide covers enabling GTIDs, CHANGE MASTER TO MASTER_AUTO_POSITION, and failover.

A production guide to MySQL slow query log — enabling with long_query_time and log_queries_not_using_indexes, analyzing with pt-query-digest, reading EXPLAIN output, and fixing full table scans and N+1 loops.

Optimize MySQL connection management for maximum throughput. Learn connection pooling with HikariCP, ProxySQL load balancing, and thread pool configuration.

MySQL 8.0 finally supports true descending indexes — eliminating the filesort that MySQL 5.7 required when sorting results in descending order. Here's how descending indexes work and when to add them.

Build fault-tolerant MySQL clusters with Group Replication. Learn multi-primary vs single-primary modes, conflict resolution, network partitioning handling, and failover strategies.