InnoDB Introduction

An overview of the InnoDB storage engine, detailing its support for ACID transactions, row-level locking, and crash recovery.

Overview

MariaDB Enterprise Server uses the InnoDB storage engine by default. InnoDB is a general purpose transactional storage engine that is performant, ACID-compliant, and well-suited for most workloads.

Benefits

The InnoDB storage engine:

• Is available with all versions of MariaDB Enterprise Server and MariaDB Community Server.

• Is a general purpose storage engine.

• Is transactional and well-suited for online transactional processing (OLTP) workloads.

• Is ACID-compliant.

• Performs well for mixed read-write workloads.

• Supports online DDL.

Feature Summary

Feature	Detail	Resources
Storage Engine	InnoDB
Availability	All ES and CS versions	MariaDB Enterprise Server
Workload Optimization	Transactional
Table Orientation	Row
Default Row Format	Dynamic	InnoDB Row Formats InnoDB Dynamic Row Format
ACID-compliant	Yes
XA Transactions	Yes
Primary Keys	Yes	InnoDB Primary Keys
Auto-Increment	Yes	InnoDB AUTO_INCREMENT Columns
Sequences	Yes	InnoDB Sequences
Foreign Keys	Yes	InnoDB Foreign Keys
Indexes	Yes	InnoDB Indexes
Secondary Indexes	Yes	InnoDB Secondary Indexes
Unique Indexes	Yes	InnoDB Unique Indexes
Full-text Search	Yes	InnoDB Full-text Indexes
Spatial Indexes	Yes	InnoDB Spatial Indexes
Compression	Yes	Configure InnoDB Page Compression
Data-at-Rest Encryption	Yes
High Availability (HA)	Yes	• MariaDB Replication • Galera Cluster
Main Memory Caching	Yes	InnoDB Buffer Pool
Transaction Logging	Yes	• InnoDB Redo Log (Crash Safety) • InnoDB Undo Log (MVCC)
Garbage Collection	Yes	InnoDB Purge Threads
Online Schema changes	Yes	InnoDB Schema Changes
Non-locking Reads	Yes
Row Locking	Yes

Examples

Creating an InnoDB Table

CREATE DATABASE hq_sales;

CREATE TABLE hq_sales.invoices (
   invoice_id BIGINT UNSIGNED AUTO_INCREMENT NOT NULL,
   branch_id INT NOT NULL,
   customer_id INT,
   invoice_date DATETIME(6),
   invoice_total DECIMAL(13, 2),
   payment_method ENUM('NONE', 'CASH', 'WIRE_TRANSFER', 'CREDIT_CARD', 'GIFT_CARD'),
   PRIMARY KEY(invoice_id)
) ENGINE = InnoDB;

SELECT TABLE_SCHEMA, TABLE_NAME, ENGINE
FROM information_schema.TABLES
WHERE TABLE_SCHEMA='hq_sales'
AND TABLE_NAME='invoices';
+--------------+------------+--------+
| TABLE_SCHEMA | TABLE_NAME | ENGINE |
+--------------+------------+--------+
| hq_sales     | invoices   | InnoDB |
+--------------+------------+--------+

Resources

Architecture

• Background Thread Pool

• Buffer Pool

• I/O Threads

• Purge Threads

• Redo Log

• Row Formats

• Undo Log

Operations

• Configure Page Compression

• Configure the Buffer Pool

• Configure the I/O Threads

• Configure the Purge Threads

• Configure the Redo Log

• Configure the Undo Log

• Schema Changes

MariaDB documentation

• InnoDB

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