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<p>allows multiple parents.  It was most popular before being replaced by the relational model, and is defined by the <a href="page.php?w=CODASYL">CODASYL</a> specification.</p>

<p>The network model organizes data using two fundamental concepts, called records and sets. Records contain fields (which may be organized hierarchically, as in the programming language <a href="page.php?w=COBOL">COBOL</a>). Sets (not to be confused with mathematical sets) define <a href="page.php?w=One-to-many_%28data_model%29">one-to-many</a> relationships between records:</p><p>
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