This article provides a comprehensive overview of InnoDB's transaction lock subsystem in MySQL, explaining row‑level and table‑level lock types, their internal implementations, lock‑compatibility rules, practical SQL examples, and common deadlock scenarios with detailed code illustrations.
This article explains how InnoDB implements row‑level locking in MySQL, detailing the lock types (record, gap, next‑key), the scenarios that trigger each lock, how unique and non‑unique indexes affect locking, and provides step‑by‑step commands and examples for analyzing locks with performance_schema.
This comprehensive guide explains how MySQL's InnoDB engine applies row‑level locks—including shared, exclusive, gap, and next‑key locks—based on different SQL statements, isolation levels, and index types, and shows how to analyze and avoid phantom reads with practical experiments.
While InnoDB’s row‑level locking generally outperforms MyISAM’s table‑level locking under high concurrency, misuse can negate its advantages; this guide explains why indexing, precise lock scopes, minimal range queries, smaller transactions, and lower isolation levels are essential for optimal InnoDB performance.
