The JusDB Database Engineering Blog

MySQL 8.0 introduced EXPLAIN FORMAT=TREE — a hierarchical, human-readable query plan format that reveals join order, access methods, and cost estimates in a way that the traditional tabular EXPLAIN cannot.

MySQL 8.0 introduced multi-valued indexes — allowing you to index individual elements of a JSON array so queries using MEMBER OF or JSON_OVERLAPS can use an index.

A production guide to zero-downtime database migrations — why ALTER TABLE causes downtime, the Expand-Contract pattern, safe migration patterns for PostgreSQL and MySQL, and tooling with Flyway, Liquibase, pt-osc, and gh-ost.

Deploy Vitess for horizontal MySQL sharding — VSchema design, vtgate routing, and migration from single-instance MySQL

ProxySQL pools thousands of application connections into a small backend pool, splits reads to replicas automatically, and lets you change routing without touching application code or restarting MySQL.

Master AWS RDS connection limits for MySQL and PostgreSQL. Learn max_connections calculation, connection pooling strategies, and optimization techniques.

Debezium reads MySQL binary logs and PostgreSQL WAL to stream every row-level change as a Kafka event in near real-time — replacing nightly batch ETL with sub-second data propagation.

A complete guide to MySQL JSON functions — JSON column type, JSON_EXTRACT and arrow operators, JSON_SET vs JSON_INSERT vs JSON_REPLACE vs JSON_MERGE_PATCH, functional indexes, and multi-valued indexes for arrays.

Master MySQL index data structures and optimization strategies. Learn B+ tree internals, index selection, covering indexes, and real-world performance case studies.

A production guide to AWS RDS Proxy — how it works, when to use it, IAM authentication setup, and the connection pool sizing rules that prevent Lambda-induced database overload.

Build a MySQL CDC pipeline using binlog and Kafka — Debezium, Maxwell, or Canal — trade-offs and production setup

Reduce AWS RDS MySQL costs by 40-60% with proven optimization strategies. Learn Reserved Instance planning, right-sizing, storage optimization, and read replica strategies.