mirror of https://github.com/postgres/postgres
Ooops, fix busted markup.
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@ -1,5 +1,5 @@
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<!--
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$Header: /cvsroot/pgsql/doc/src/sgml/syntax.sgml,v 1.62 2002/06/15 21:28:55 tgl Exp $
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$Header: /cvsroot/pgsql/doc/src/sgml/syntax.sgml,v 1.63 2002/06/15 22:15:03 tgl Exp $
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-->
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<chapter id="sql-syntax">
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@ -1471,11 +1471,11 @@ SELECT somefunc() OR true;
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be used. For example, this is an untrustworthy way of trying to
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avoid division by zero in a WHERE clause:
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<programlisting>
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SELECT ... WHERE x <> 0 AND y/x > 1.5;
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SELECT ... WHERE x <> 0 AND y/x > 1.5;
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</programlisting>
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but this is safe:
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<programlisting>
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SELECT ... WHERE CASE WHEN x <> 0 THEN y/x > 1.5 ELSE false END;
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SELECT ... WHERE CASE WHEN x <> 0 THEN y/x > 1.5 ELSE false END;
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</programlisting>
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A CASE construct used in this fashion will defeat optimization attempts,
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so it should only be done when necessary.
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