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Minor copy-editing.

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This commit is contained in:
Tom Lane
2003-08-14 23:13:27 +00:00
parent b72c1b9f63
commit 0684043e39
4 changed files with 42 additions and 39 deletions
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23
doc/src/sgml/syntax.sgml
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@@ -1,5 +1,5 @@
<!--
$Header: /cvsroot/pgsql/doc/src/sgml/syntax.sgml,v 1.81 2003/08/09 22:50:22 tgl Exp $
$Header: /cvsroot/pgsql/doc/src/sgml/syntax.sgml,v 1.82 2003/08/14 23:13:27 tgl Exp $
-->
<chapter id="sql-syntax">
@@ -450,14 +450,7 @@ CAST ( '<replaceable>string</replaceable>' AS <replaceable>type</replaceable> )
'{{1,2,3},{4,5,6},{7,8,9}}'
</programlisting>
This constant is a two-dimensional, 3-by-3 array consisting of three
subarrays of integers.
</para>
<para>
Individual array elements can be placed between double-quote
marks (<literal>"</literal>) <!-- " --> to avoid ambiguity
problems with respect to whitespace. Without quote marks, the
array-value parser will skip leading whitespace.
subarrays of integers. For more information see <xref linkend="arrays">.
</para>
<para>
@@ -1190,8 +1183,10 @@ CAST ( <replaceable>expression</replaceable> AS <replaceable>type</replaceable>
one of the two standard cast syntaxes is used to do a run-time
conversion, it will internally invoke a registered function to
perform the conversion. By convention, these conversion functions
have the same name as their output type, but this is not something
that a portable application should rely on.)
have the same name as their output type, and thus the <quote>function-like
syntax</> is nothing more than a direct invocation of the underlying
conversion function. Obviously, this is not something that a portable
application should rely on.)
</para>
</sect2>
@@ -1349,8 +1344,10 @@ SELECT ... WHERE x &lt;&gt; 0 AND y/x &gt; 1.5;
<programlisting>
SELECT ... WHERE CASE WHEN x &lt;&gt; 0 THEN y/x &gt; 1.5 ELSE false END;
</programlisting>
A <literal>CASE</> construct used in this fashion will defeat optimization attempts,
so it should only be done when necessary.
A <literal>CASE</> construct used in this fashion will defeat optimization
attempts, so it should only be done when necessary. (In this particular
example, it would doubtless be best to sidestep the problem by writing
<literal>y &gt; 1.5*x</> instead.)
</para>
</sect2>
</sect1>