Movatterモバイル変換

MySQL 8.4 Reference Manual

17.1 Introduction to InnoDB

17.1.1 Benefits of Using InnoDB Tables
17.1.2 Best Practices for InnoDB Tables
17.1.3 Verifying that InnoDB is the Default Storage Engine
17.1.4 Testing and Benchmarking with InnoDB

InnoDB is a general-purpose storage engine that balances high reliability and high performance. In MySQL 8.4,InnoDB is the default MySQL storage engine. Unless you have configured a different default storage engine, issuing aCREATE TABLE statement without anENGINE clause creates anInnoDB table.

Key Advantages of InnoDB

Its DML operations follow the ACID model, with transactions featuring commit, rollback, and crash-recovery capabilities to protect user data. SeeSection 17.2, “InnoDB and the ACID Model”.
Row-level locking and Oracle-style consistent reads increase multi-user concurrency and performance. SeeSection 17.7, “InnoDB Locking and Transaction Model”.
InnoDB tables arrange your data on disk to optimize queries based on primary keys. EachInnoDB table has a primary key index called the clustered index that organizes the data to minimize I/O for primary key lookups. SeeSection 17.6.2.1, “Clustered and Secondary Indexes”.
To maintain data integrity,InnoDB supportsFOREIGN KEY constraints. With foreign keys, inserts, updates, and deletes are checked to ensure they do not result in inconsistencies across related tables. SeeSection 15.1.20.5, “FOREIGN KEY Constraints”.

Table 17.1 InnoDB Storage Engine Features

Feature	Support
B-tree indexes	Yes
Backup/point-in-time recovery (Implemented in the server, rather than in the storage engine.)	Yes
Cluster database support	No
Clustered indexes	Yes
Compressed data	Yes
Data caches	Yes
Encrypted data	Yes (Implemented in the server via encryption functions; In MySQL 5.7 and later, data-at-rest encryption is supported.)
Foreign key support	Yes
Full-text search indexes	Yes (Support for FULLTEXT indexes is available in MySQL 5.6 and later.)
Geospatial data type support	Yes
Geospatial indexing support	Yes (Support for geospatial indexing is available in MySQL 5.7 and later.)
Hash indexes	No (InnoDB utilizes hash indexes internally for its Adaptive Hash Index feature.)
Index caches	Yes
Locking granularity	Row
MVCC	Yes
Replication support (Implemented in the server, rather than in the storage engine.)	Yes
Storage limits	64TB
T-tree indexes	No
Transactions	Yes
Update statistics for data dictionary	Yes

To compare the features ofInnoDB with other storage engines provided with MySQL, see theStorage Engine Features table inChapter 18,Alternative Storage Engines.

InnoDB Enhancements and New Features

For information aboutInnoDB enhancements and new features, refer to:

TheInnoDB enhancements list inSection 1.4, “What Is New in MySQL 8.4 since MySQL 8.0”.
TheRelease Notes.

Additional InnoDB Information and Resources

ForInnoDB-related terms and definitions, see theMySQL Glossary.
For a forum dedicated to theInnoDB storage engine, seeMySQL Forums::InnoDB.
InnoDB is published under the same GNU GPL License Version 2 (of June 1991) as MySQL. For more information on MySQL licensing, seehttp://www.mysql.com/company/legal/licensing/.

PREV HOME UP NEXT