JD Tech

Oct 15, 2026 · Databases

Building a Custom Database Sharding Component with MyBatis: Migration Strategies & SQL Rewriting

This article details the design and implementation of a custom database sharding component built on MyBatis plugin architecture, covering sharding strategies, read/write policies (double-write/double-read), SQL parsing and rewriting for COUNT/SUM/ORDER BY, routing algorithms with distributed locks, parameter mapping handling, and solutions to migration challenges like ORDER BY alias errors and aggregate query merging.