InnoDB Gap Lock Mechanism Gap locks are index interval locks that address phantom reads, active exclusively in InnoDB’s REPEATABLE READ isolation level. Instead of targeting existing index entries, they block operations on open ranges between index records, excluding the records themselves. For a ta...
Fundamental Database Concepts Index Column Limits A single index in MySQL can encompass a maximum of 16 columns. Storage Engines MySQL utilizes storage engines to manage data storage, indexing, and retrieval mechanisms. The primary engines include: InnoDB: The default engine since version 5.5.5. It...
ACID Principles of Database Transactions A transaction represents a cohesive unit of database operations that must execute entirely or not at all. This unit adheres to four fundamental principles, commonly abbreviated as ACID. Atomicity: All operations within the work unit are treated as a single in...
MySQL implements various lock types to manage concurrency and ensure data consistency. Locks are categorized by granularity: global, table-level, and row-level. Global Lock A global lock restricts the entire database instance to read-only mode, blocking DML write statements, DDL operations, and tran...