Tagged articles

RR isolation

3 articles · Page 1 of 1

Sep 7, 2026 · Databases

MySQL MVCC Deep Dive: Lock-Free Reads, Isolation Levels & Phantom Read Mechanics

This article explains MySQL's MVCC mechanism in InnoDB, detailing how hidden fields, undo logs, and Read Views enable lock-free snapshot reads, the differences between RC and RR isolation levels, why MVCC prevents non-repeatable reads but not phantom reads, and common pitfalls like long transactions causing undo log bloat.

InnoDBMVCCPhantom Read

0 likes · 11 min read

MySQL MVCC Deep Dive: Lock-Free Reads, Isolation Levels & Phantom Read Mechanics

Aikesheng Open Source Community

Jun 28, 2023 · Databases

Analyzing Slow UPDATE Locks in MySQL 5.7 and Optimizing with Indexes and Optimizer Trace

The article investigates why an UPDATE statement on a MySQL 5.7 InnoDB table with RR isolation experiences high lock time, demonstrates how missing indexes cause full‑table scans and blocking, and shows how adding an index and using optimizer trace can diagnose and resolve the issue.

InnoDBMySQLRR isolation

0 likes · 8 min read

Analyzing Slow UPDATE Locks in MySQL 5.7 and Optimizing with Indexes and Optimizer Trace

Youzan Coder

Jan 30, 2019 · Operations

Why Do MySQL RR Transactions Deadlock? A Deep Dive into Index Locking

This article examines two MySQL deadlock scenarios under REPEATABLE READ isolation—one with a non‑unique index and another with a unique index—by presenting table definitions, test data, raw deadlock logs, and step‑by‑step analysis of lock acquisition and waiting, ultimately offering practical recommendations to avoid such deadlocks.

InnoDBMySQLRR isolation

0 likes · 12 min read

Why Do MySQL RR Transactions Deadlock? A Deep Dive into Index Locking