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<p><big>Relational model</big></p>
<p>The <a href="page.php?w=relational_model">relational model</a> was introduced by <a href="page.php?w=E.F._Codd">E.F. Codd</a> in 1970 as a way to make database management systems more independent of any particular application. It is a mathematical model defined in terms of <a href="page.php?w=predicate_logic">predicate logic</a> and <a href="page.php?w=set_theory">set theory</a>, and implementations of it have been used by mainframe, midrange and microcomputer systems.</p>

<p>The products that are generally referred</p><p>
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