This article investigates a slow‑SQL incident caused by the TDDL optimizer reordering a MySQL query, analyzes why the optimizer chose an inefficient index, demonstrates how to verify and force the correct index, and proposes better index and partition‑key designs for optimal performance.
This article examines the storage challenges faced by large‑scale internet services and evaluates popular MySQL middleware solutions—ProxySQL, MaxScale, DBProxy, MyCat, and TDDL—by mapping business requirements to their core features and capabilities.
This article explains how to handle multi-table cross-database transactions by aligning sharding strategies for related tables, using a case study of shop_order_detail and shop_order_stat, and provides detailed formulas and TDDL configuration code to ensure consistent routing within the same database shard.
This article explains what database sharding (splitting databases and tables) is, why it improves performance and availability, how to choose between horizontal and vertical partitioning, design ID generation, handle distributed transactions, migrate data smoothly, and configure Alibaba's TDDL middleware with practical code examples.
This article recounts the 2007 challenges faced by Taobao's monolithic MySQL setup and explains how the TDDL middleware introduced SQL optimization, sharding, read‑write separation, caching, and dynamic scaling to transform the system into a distributed, high‑performance database solution.
Xianyu migrated its tens‑billion‑row product database from a shared MySQL cluster to an isolated instance by refactoring with dual‑write, employing TDDL for sharding and sequence management, and using Alibaba Cloud DTS for full‑load, incremental sync, consistency verification, and a no‑data‑loss rollback, achieving seamless, user‑transparent migration and improved stability.
This article traces the evolution of Alibaba’s distributed data layer—from the early Cobar system to the modern TDDL framework and DRDS service—explaining their architectures, limitations, sharding principles, transaction‑boundary strategies, heterogeneous index tables, and the Jingwei data‑replication platform that together enable seamless scaling and high‑performance SQL processing across thousands of databases.
