A database engine is the underlying software component that a database management system

Database management system

A database management system is a software package with computer programs that control the creation, maintenance, and use of a database. It allows organizations to conveniently develop databases for various applications by database administrators and other specialists. A database is an integrated...

 (DBMS) uses to create, read, update and delete (CRUD) data

Data

The term data refers to qualitative or quantitative attributes of a variable or set of variables. Data are typically the results of measurements and can be the basis of graphs, images, or observations of a set of variables. Data are often viewed as the lowest level of abstraction from which...

 from a database

Database

A database is an organized collection of data for one or more purposes, usually in digital form. The data are typically organized to model relevant aspects of reality , in a way that supports processes requiring this information...

.
Most database management systems include their own application programming interface

Application programming interface

An application programming interface is a source code based specification intended to be used as an interface by software components to communicate with each other...

 (API) that allows the user to interact with their underlying engine without going through the user interface of the DBMS.

Many of the modern DBMS support multiple database engines within the same database. For example, MySQL

MySQL

MySQL officially, but also commonly "My Sequel") is a relational database management system that runs as a server providing multi-user access to a number of databases. It is named after developer Michael Widenius' daughter, My...

 supports InnoDB

InnoDB

InnoDB is the default storage engine for MySQL as of MySQL 5.5. It provides the standard ACID-compliant transaction features, along with foreign key support...

 as well as MyISAM

MyISAM

MyISAM was the default storage engine for the MySQL relational database management system versions prior to 5.5 . It is based on the older ISAM code but has many useful extensions. The major deficiency of MyISAM is the absence of transactions support...

.

Some database engines are transactional

Database transaction

A transaction comprises a unit of work performed within a database management system against a database, and treated in a coherent and reliable way independent of other transactions...

.

Name	Free	Transactional
Aria	GPL
BlitzDB	GPL
Falcon Falcon (storage engine) Falcon was a transactional storage engine being developed for the MySQL relational database management system. Development was stopped after Oracle purchased MySQL. It was based on the Netfrastructure database engine...	GPL
InnoDB InnoDB InnoDB is the default storage engine for MySQL as of MySQL 5.5. It provides the standard ACID-compliant transaction features, along with foreign key support...	GPL
MyISAM MyISAM MyISAM was the default storage engine for the MySQL relational database management system versions prior to 5.5 . It is based on the older ISAM code but has many useful extensions. The major deficiency of MyISAM is the absence of transactions support...	GPL
XtraDB	GPL

See also

• Aria (storage engine)
• Btrieve's Micro-Kernel Database Engine
• Berkeley DB
  Berkeley DB
  Berkeley DB is a computer software library that provides a high-performance embedded database for key/value data. Berkeley DB is a programmatic software library written in C with API bindings for C++, PHP, Java, Perl, Python, Ruby, Tcl, Smalltalk, and most other programming languages...
  
  
• c-treeACE Database Engine
  C-tree
  c-treeACE is a cross-platform database engine developed by FairCom Corporation. Software developers typically embed the c-treeACE engine within the applications that they create and then deploy the application and engine together as an integrated solution....
  
  
• FLAIM Database Engine
• InnoDB
  InnoDB
  InnoDB is the default storage engine for MySQL as of MySQL 5.5. It provides the standard ACID-compliant transaction features, along with foreign key support...
  
  
• Microsoft Jet Database Engine
  Microsoft Jet Database Engine
  The Microsoft Jet Database Engine is a database engine on which several Microsoft products have been built. A database engine is the underlying component of a database, a collection of information stored on a computer in a systematic way...
  
  
• MyISAM
  MyISAM
  MyISAM was the default storage engine for the MySQL relational database management system versions prior to 5.5 . It is based on the older ISAM code but has many useful extensions. The major deficiency of MyISAM is the absence of transactions support...
  
  
• MySQL Cluster
  MySQL Cluster
  MySQL Cluster is a technology which provides shared-nothing clustering capabilities for the MySQL database management system. It was first included in the production release of MySQL 4.1 in November 2004. It is designed to provide high availability and high performance, while allowing for nearly...
  
  , on the NDB storage engine of MySQL
  MySQL
  MySQL officially, but also commonly "My Sequel") is a relational database management system that runs as a server providing multi-user access to a number of databases. It is named after developer Michael Widenius' daughter, My...
  
  

External links

• http://dev.mysql.com/tech-resources/articles/storage-engine/part_3.html