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<!--
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- $Header: /cvsroot/pgsql/doc/src/sgml/ref/create_operator.sgml,v 1.16 2000/09/12 20:52:08 momjian Exp $
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+ $Header: /cvsroot/pgsql/doc/src/sgml/ref/create_operator.sgml,v 1.17 2000/10/10 04:42:43 momjian Exp $
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Postgres documentation
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-->
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@@ -248,13 +248,13 @@ CREATE
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Hence, the query optimizer could freely convert:
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<programlisting>
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- box '((0,0),(1,1))' >>> MYBOXES.description
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+ box '((0,0), (1,1))' >>> MYBOXES.description
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</programlisting>
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to
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<programlisting>
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- MYBOXES.description <<< box '((0,0),(1,1))'
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+ MYBOXES.description <<< box '((0,0), (1,1))'
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</programlisting>
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</para>
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<para>
@@ -269,11 +269,11 @@ MYBOXES.description <<< box '((0,0),(1,1))'
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equal, !==.
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The negator link allows the query optimizer to simplify
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<programlisting>
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- NOT MYBOXES.description === box '((0,0),(1,1))'
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+ NOT MYBOXES.description === box '((0,0), (1,1))'
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</programlisting>
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to
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<programlisting>
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- MYBOXES.description !== box '((0,0),(1,1))'
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+ MYBOXES.description !== box '((0,0), (1,1))'
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</programlisting>
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</para>
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<para>
@@ -331,7 +331,7 @@ MYBOXES.description !== box '((0,0),(1,1))'
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The RESTRICT and JOIN options assist the query optimizer in estimating
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result sizes. If a clause of the form:
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<programlisting>
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- MYBOXES.description <<< box '((0,0),(1,1))'
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+ MYBOXES.description <<< box '((0,0), (1,1))'
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</programlisting>
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is present in the qualification,
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then <productname>Postgres</productname> may have to
@@ -342,7 +342,7 @@ MYBOXES.description <<< box '((0,0),(1,1))'
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<command>CREATE FUNCTION</command>) which accepts arguments of the correct
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data types and returns a floating point number. The
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query optimizer simply calls this function, passing the
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- parameter <literal>((0,0),(1,1))</literal> and multiplies the result by the relation
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+ parameter <literal>((0,0), (1,1))</literal> and multiplies the result by the relation
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size to get the expected number of instances.
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</para>
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<para>
@@ -356,11 +356,11 @@ MYBOXES.description <<< box '((0,0),(1,1))'
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<para>
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The difference between the function
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<programlisting>
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- my_procedure_1 (MYBOXES.description, box '((0,0),(1,1))')
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+ my_procedure_1 (MYBOXES.description, box '((0,0), (1,1))')
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</programlisting>
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and the operator
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<programlisting>
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- MYBOXES.description === box '((0,0),(1,1))'
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+ MYBOXES.description === box '((0,0), (1,1))'
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</programlisting>
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is that <productname>Postgres</productname>
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attempts to optimize operators and can
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