What are the different storage engines supported by MySQL?

MySQL supports various storage engines, each with its own unique features, performance characteristics, and use cases. Here's a technical breakdown of some of the most commonly used storage engines supported by MySQL:

  1. InnoDB:
    • InnoDB is the default storage engine for MySQL as of version 5.5. It provides ACID (Atomicity, Consistency, Isolation, Durability) compliance, transactions, and foreign key constraints.
    • InnoDB utilizes clustered indexes, where the primary key index is the actual data storage structure.
    • It supports row-level locking for concurrent access, improving performance in high-concurrency environments.
    • InnoDB is well-suited for OLTP (Online Transaction Processing) workloads and applications that require high reliability and transactional support.
  2. MyISAM:
    • MyISAM was the default storage engine in older versions of MySQL but has been largely superseded by InnoDB.
    • MyISAM doesn't support transactions or foreign key constraints, making it less suitable for applications that require strong data integrity guarantees.
    • It offers table-level locking, which can lead to contention in high-concurrency scenarios.
    • MyISAM is known for its fast read operations, making it suitable for read-heavy workloads such as data warehousing or reporting.
    • The MEMORY engine stores tables entirely in memory, making it extremely fast for read and write operations.
    • As the data is stored in memory, it's volatile and gets lost on server restarts or crashes.
    • MEMORY tables support hash and B-tree indexes but don't support features like transactions or foreign keys.
    • It's useful for caching, temporary tables, or other scenarios where performance is critical and data persistence is not a requirement.
  4. CSV:
    • The CSV engine stores data in text files using comma-separated values (CSV) format.
    • It's suitable for exchanging data with external systems or for storing non-critical data.
    • CSV tables don't support indexes, transactions, or foreign keys.
    • It's not suitable for high-concurrency or high-volume transactional workloads due to its simplistic nature.
    • The ARCHIVE engine is optimized for storing large volumes of data with minimal storage space.
    • It achieves compression by storing rows in a highly compressed format.
    • ARCHIVE tables support INSERT and SELECT operations but don't support UPDATE or DELETE operations.
    • It's useful for storing historical data or log files where fast retrieval is not a primary concern.
  6. NDB (MySQL Cluster):
    • The NDB storage engine is part of the MySQL Cluster technology, which enables high availability and scalability through shared-nothing clustering.
    • It's designed for distributed, high-availability environments where data needs to be distributed across multiple nodes.
    • NDB tables support ACID transactions and are highly fault-tolerant.
    • It's suitable for applications requiring high availability, real-time performance, and automatic sharding of data.