<span class="mw-page-title-main">Object–relational database</span>

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Object–relational database

<p>An <b>object–relational database</b> (<b>ORD</b>), or <b>object–relational database management system</b> (<b>ORDBMS</b>), is a <a href="/en/Database_management_system" title="Database management system" class="mw-redirect wl">database management system</a> (DBMS) similar to a <a href="/en/Relational_database" title="Relational database" class="wl">relational database</a>, but with an <a href="/en/Object_database" title="Object database" class="wl">object-oriented database model</a>: objects, classes and inheritance are directly supported in <a href="/en/Database_schema" title="Database schema" class="wl">database schemas</a> and in the <a href="/en/Query_language" title="Query language" class="wl">query language</a>.  In addition, just as with pure relational systems, it supports extension of the <a href="/en/Data_model" title="Data model" class="wl">data model</a> with custom <a href="/en/Data_type" title="Data type" class="wl">data types</a> and <a href="/en/Method_(computer_science)" title="Method (computer science)" class="mw-redirect wl">methods</a>.</p>
<figure class="wiki-thumb"><a href="/en/File:Object-Oriented_Model.svg" class="mw-file-description image media-thumb" data-hash="File:Object-Oriented_Model.svg"><img loading="lazy" src="//upload.wikimedia.org/wikipedia/commons/thumb/7/7c/Object-Oriented_Model.svg/320px-Object-Oriented_Model.svg.png" decoding="async" data-file-width="598" data-file-height="442" data-file-type="drawing" height="237" width="320" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/7/7c/Object-Oriented_Model.svg/480px-Object-Oriented_Model.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/7/7c/Object-Oriented_Model.svg/640px-Object-Oriented_Model.svg.png 2x" alt="Object-Oriented_Model.svg"></a><figcaption>Example of an object-oriented database model<span class="mw-ref reference" id="cite_ref-USDT01_1-0"><a href="#cite_note-USDT01-1" style="counter-reset: mw-Ref 1;"><span class="mw-reflink-text">[1]</span></a></span></figcaption></figure>

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<div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none" about="#mwt5">Database management system</div>
<p>An object–relational database can be said to provide a middle ground between relational databases and <a href="/en/Object_database" title="Object database" class="wl">object-oriented databases</a>. In object–relational databases, the approach is essentially that of relational databases: the data resides in the database and is manipulated collectively with queries in a query language; at the other extreme are OODBMSes in which the database is essentially a persistent object store for software written in an <a href="/en/Object-oriented_programming_language" title="Object-oriented programming language" class="mw-redirect wl">object-oriented programming language</a>, with a programming <a href="/en/API" title="API" class="wl">API</a> for storing and retrieving objects, and little or no specific support for querying.</p>



An object–relational database , or object–relational database management system , is a database management system similar to a relational database, but with an object-oriented database model: objects, classes and inheritance are directly supported in database schemas and in the query language.  In addition, just as with pure relational systems, it supports extension of the data model with custom data types and methods. An object–relational database can be said to provide a middle ground between relational databases and object-oriented databases. In object–relational databases, the approach is essentially that of relational databases: the data resides in the database and is manipulated collectively with queries in a query language; at the other extreme are OODBMSes in which the database is essentially a persistent object store for software written in an object-oriented programming language, with a programming API for storing and retrieving objects, and little or no specific support for querying. 