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This article provides a comprehensive index of a MySQL internals series covering the transaction, lock, and undo modules, detailing each sub‑topic such as transaction initialization, two‑phase commit, various lock types, deadlock handling, and undo log management across numerous linked articles.
The article explains how InnoDB handles transaction commit by modifying Insert and Update Undo segment states, generating a transaction commit number, adding rollback segments to the purge queue, and finally cleaning or caching Undo segments based on their usage and state.
This article explains how to read and parse the Undo log generated by a DELETE operation in MySQL 8.0.32 InnoDB, covering preparation, log extraction, detailed field parsing, locating the primary index record, and the step‑by‑step rollback of secondary and primary index records.
This article explains how MySQL 8.0 InnoDB generates and stores Delete Undo logs, detailing the log structure, field meanings, type_flag and info_bits decoding, address composition via DB_ROLL_PTR, and provides concrete SQL examples and shell calculations to illustrate the process.
After publishing 50 installments of the 'MySQL Core Modules' series covering transactions, locks, and undo, the author expresses gratitude to readers and the community, outlines upcoming articles on Undo, MVCC, and Redo, and reviews past content while planning a compiled book.
This article explains how MySQL 8.0.32's InnoDB engine generates, reads, and parses Undo logs for an UPDATE operation, and details the step‑by‑step process of locating the primary record, constructing a rollback record, and restoring both secondary and primary index entries.
This article explains how MySQL 8.0.32 InnoDB generates and stores Update undo logs, detailing the log format, the meaning of each field, how to interpret the log address, and provides concrete SQL examples and shell calculations for practical insight.
This article explains the complete InnoDB undo‑log rollback process on MySQL 8.0, covering preparation, reading and parsing undo logs, constructing primary‑key index records, and the detailed steps for deleting secondary and primary index entries during a transaction rollback.
This article explains how MySQL 8.0.32 InnoDB generates and stores Insert Undo logs, detailing their binary format, field meanings, example values, and how the hidden DB_ROLL_PTR field encodes the log address, with accompanying SQL and shell examples.
This article explains the four‑layer logical structure of InnoDB Undo logs—Undo pages, Undo segments, rollback segments, and Undo tablespaces—detailing their roles, management, related system variables, and how they affect transaction rollback and storage in MySQL 8.0.32.
This article provides a concise English recap of the 27 previously published InnoDB lock module articles, covering theoretical concepts such as table and row locks, lock waiting, deadlock handling, and practical scenarios like lock behavior during inserts and duplicate key operations.
This article explains the core components of MySQL's InnoDB storage engine—including undo log, redo log, buffer pool, change buffer, and binlog—detailing their roles in data writing, crash recovery, MVCC, and master‑slave synchronization, and describing related flushing strategies and LRU management.
The article analyzes a MySQL 5.7 replication bug where, after consecutive crashes, the slave ends up with more GTIDs than the master because the last binlog’s GTIDs are not persisted, and demonstrates the problem using GDB debugging and step‑by‑step reproduction.
This article explains how InnoDB simulates deadlocks, how the ib_srv_lock_to background thread checks for deadlocks, how it builds lock‑wait snapshots, constructs lock‑wait graphs, calculates transaction weights, and finally resolves deadlocks, illustrated with detailed SQL examples and code snippets.
This article explains the inner workings of InnoDB’s lock‑wait timeout thread, detailing how it scans waiting slots, identifies timed‑out transactions, processes timeout logic, and notifies the affected transactions, while also covering related data structures and configuration variables.
This article explains the slow‑path row‑locking algorithm used by InnoDB in MySQL 8.0.32, detailing how the engine checks whether a transaction already holds a lock, determines if it must wait, reuses existing lock structures, and allocates new ones when necessary.
This article explains how InnoDB implements row locking by dividing the process into fast and slow paths, describing the hash‑based lock table, token acquisition, lock‑structure creation, bitmap handling, and the conditions that trigger slow‑lock logic.
This article explains the structure and components of InnoDB's lock module, including the global lock_sys object, its hash tables, latch mechanisms, waiting thread slots, and related attributes, with detailed code examples and diagrams to illustrate how row and table locks are managed.
This article examines the shared and distinct fields of InnoDB's table‑lock and row‑lock structures in MySQL 8.0.32, explains the layout of the lock_t, lock_table_t and lock_rec_t structs, decodes the type_mode bit‑field, and discusses how InnoDB merges compatible row‑locks using a bitmap memory area.
This article explains the architecture of MySQL's InnoDB storage engine locks, covering server‑level metadata locks, table‑level shared and exclusive locks, intent locks, and the three modes of AUTO‑INC locks, with practical SQL examples and performance‑schema queries.