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Fixups in content and markup for 7.0 release.
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@ -1,5 +1,5 @@
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<!--
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$Header: /cvsroot/pgsql/doc/src/sgml/sql.sgml,v 1.8 2000/04/07 13:30:58 thomas Exp $
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$Header: /cvsroot/pgsql/doc/src/sgml/sql.sgml,v 1.9 2000/05/02 20:01:52 thomas Exp $
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-->
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<chapter id="sql">
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@ -24,7 +24,7 @@ $Header: /cvsroot/pgsql/doc/src/sgml/sql.sgml,v 1.8 2000/04/07 13:30:58 thomas E
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<para>
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<acronym>SQL</acronym> has become the most popular relational query
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language.
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The name <quote><acronym>SQL</acronym></quote> is an abbreviation for
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The name "<acronym>SQL</acronym>" is an abbreviation for
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<firstterm>Structured Query Language</firstterm>.
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In 1974 Donald Chamberlin and others defined the
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language SEQUEL (<firstterm>Structured English Query
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@ -759,8 +759,8 @@ t<subscript>r</subscript>(A,B)=t∧t<subscript>r</subscript>(C,D)=t<subscript>
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can be formulated using relational algebra can also be formulated
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using the relational calculus and vice versa.
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This was first proved by E. F. Codd in
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1972. This proof is based on an algorithm (<quote>Codd's reduction
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algorithm</quote>) by which an arbitrary expression of the relational
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1972. This proof is based on an algorithm ("Codd's reduction
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algorithm") by which an arbitrary expression of the relational
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calculus can be reduced to a semantically equivalent expression of
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relational algebra. For a more detailed discussion on that refer to
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<xref linkend="DATE94" endterm="DATE94">
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