<!DOCTYPE html>
<html class="client-nojs vector-feature-language-in-header-enabled vector-feature-language-in-main-page-header-disabled vector-feature-page-tools-pinned-disabled vector-feature-toc-pinned-clientpref-0 vector-toc-not-available vector-feature-main-menu-pinned-disabled vector-feature-limited-width-clientpref-1 vector-feature-limited-width-content-enabled vector-feature-custom-font-size-clientpref-1 vector-feature-appearance-pinned-clientpref-0 skin-theme-clientpref-day vector-sticky-header-enabled" lang="de" dir="ltr"><head>
<meta charset="UTF-8">
<title>Object Query Language</title>
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<link rel="icon" type="image/png" href="./_res_/favicon.png">
<link rel="canonical" href="https://de.wikipedia.org/wiki/Object_Query_Language"> <link href="./_mw_/ext.pygments.css" rel="stylesheet" type="text/css">
<link href="./_mw_/ext.wikimediamessages.styles.css" rel="stylesheet" type="text/css">
<link href="./_mw_/skins.vector.icons.css" rel="stylesheet" type="text/css">
<link href="./_mw_/skins.vector.search.codex.styles.css" rel="stylesheet" type="text/css">
<link href="./_mw_/skins.vector.styles.css" rel="stylesheet" type="text/css">
<meta name="ResourceLoaderDynamicStyles" content="">
<link href="./_mw_/ext.gadget.citeRef.css" rel="stylesheet" type="text/css">
<link href="./_mw_/ext.gadget.defaultPlainlinks.css" rel="stylesheet" type="text/css">
<link href="./_mw_/ext.gadget.dewikiCommonHide.css" rel="stylesheet" type="text/css">
<link href="./_mw_/ext.gadget.dewikiCommonLayout.css" rel="stylesheet" type="text/css">
<link href="./_mw_/ext.gadget.dewikiCommonStyle.css" rel="stylesheet" type="text/css">
<link href="./_mw_/ext.gadget.dewikiDarkmode.css" rel="stylesheet" type="text/css">
<link href="./_mw_/ext.gadget.dewikiResponsive.css" rel="stylesheet" type="text/css">
<link href="./_mw_/ext.gadget.specialSearch.css" rel="stylesheet" type="text/css">
<link rel="stylesheet" type="text/css" href="./_mw_/site.styles.css">
<link rel="stylesheet" type="text/css" href="./_mw_/noscript.css">
<link rel="stylesheet" type="text/css" href="./_res_/footer.css">
<link rel="stylesheet" type="text/css" href="./_res_/vector-2022.css">
</head>
<body class="skin--responsive skin-vector skin-vector-search-vue mediawiki ltr sitedir-ltr mw-hide-empty-elt ns-0 ns-subject page-Object_Query_Language rootpage-Object_Query_Language skin-vector-2022 action-view">
<div class="mw-page-container">
<div class="mw-page-container-inner">
<div class="mw-content-container">
<main id="content" class="mw-body">
<header class="mw-body-header vector-page-titlebar">
<h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">Object Query Language</span></h1>
</header>
<a id="top"></a>
<div id="bodyContent" class="vector-body ve-init-mw-desktopArticleTarget-targetContainer" aria-labelledby="firstHeading" data-mw-ve-target-container="">
<div id="contentSub">
<div id="mw-content-subtitle"></div>
</div>
<div id="mw-content-text" class="mw-body-content mw-content-ltr" lang="de" dir="ltr"><div class="mw-content-ltr mw-parser-output" lang="de" dir="ltr"><p>Die <b>Object Query Language</b> (<b>OQL</b>) ist eine stark an <a href="SQL" title="SQL">SQL</a> angelehnte <a href="Abfragesprache" title="Abfragesprache">Abfragesprache</a> für <a href="Objektdatenbank" title="Objektdatenbank">Objektdatenbanken</a>.
</p><p>Die Sprache ist durch die <a href="Object_Database_Management_Group" title="Object Database Management Group">Object Database Management Group</a> (ODMG) standardisiert.
</p><p>Trotz der engen Anlehnung an SQL ist die Sprache wegen ihres <a href="Objektorientierte_Programmierung" title="Objektorientierte Programmierung">objektorientierten</a> Ansatzes nicht damit zu verwechseln. OQL wurde entwickelt, um die Interaktion zwischen objektorientierten Programmen und einer Datenbank zu vereinfachen. Der klassische relationale Ansatz führt zu Brüchen in der <a href="Softwarearchitektur" title="Softwarearchitektur">Softwarearchitektur</a>.
</p><p>Zur Definition der Objekte in der Datenbank kann die Object Definition Language (<a href="Object_Database_Management_Group#Komponenten" title="Object Database Management Group">ODL</a>) genutzt werden.
</p><p>Am einfachen Beispiel illustriert (Suche alle Studenten, die nicht zugleich auch <a href="Tutor" title="Tutor">Tutor</a> sind):
</p>
<div class="mw-highlight mw-highlight-lang-sql mw-content-ltr" dir="ltr"><pre><span></span><span class="k">SELECT</span><span class="w"> </span><span class="n">student</span><span class="p">.</span><span class="n">name</span>
<span class="k">FROM</span><span class="w"> </span><span class="n">student</span><span class="w"> </span><span class="k">in</span><span class="w"> </span><span class="n">StudentTUM</span>
<span class="k">WHERE</span><span class="w"> </span><span class="k">not</span><span class="w"> </span><span class="p">(</span><span class="n">student</span><span class="p">.</span><span class="n">name</span><span class="w"> </span><span class="k">in</span><span class="w"> </span><span class="k">SELECT</span><span class="w"> </span><span class="n">tutor</span><span class="p">.</span><span class="n">name</span><span class="w"> </span><span class="k">FROM</span><span class="w"> </span><span class="n">tutor</span><span class="w"> </span><span class="k">in</span><span class="w"> </span><span class="n">TAs</span><span class="p">)</span>
</pre></div>
<div class="mw-heading mw-heading2"><h2 id="Weblinks">Weblinks</h2></div>
<ul><li><a rel="nofollow" class="external text" href="https://www.odbms.org/ODMG/">www.odbms.org/ODMG/</a></li></ul></div><!--htdig_noindex--><div><div class="zim-footer">
Dieser Artikel wurde von <a class="external text" title="Zuletzt bearbeitet am 2023-04-11" href="https://de.wikipedia.org/wiki/?title=Object_Query_Language&oldid=232684609">Wikipedia</a> herausgegeben. Der Text ist unter <a class="external text" href="https://creativecommons.org/licenses/by-sa/4.0/deed.de">Creative Commons Attribution-Share Alike 4.0</a> verfügbar, sofern nicht anders angegeben. Für die Mediendateien können zusätzliche Bedingungen gelten.
</div>
</div><!--/htdig_noindex--></div>
</div>
</main>
</div>
</div>
</div>
<script src="./_webp_/webpHandler.js"></script>
</body></html>