*** pgsql/doc/src/sgml/func.sgml	2008/03/10 12:39:22	1.424
--- pgsql/doc/src/sgml/func.sgml	2008/03/23 00:24:19	1.425
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*** 1,4 ****
! <!-- $PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.423 2008/03/06 18:49:32 momjian Exp $ -->
  
   <chapter id="functions">
    <title>Functions and Operators</title>
--- 1,4 ----
! <!-- $PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.424 2008/03/10 12:39:22 tgl Exp $ -->
  
   <chapter id="functions">
    <title>Functions and Operators</title>
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*** 1263,1268 ****
--- 1263,1271 ----
      <primary>quote_literal</primary>
     </indexterm>
     <indexterm>
+     <primary>quote_nullable</primary>
+    </indexterm>
+    <indexterm>
      <primary>repeat</primary>
     </indexterm>
     <indexterm>
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*** 1523,1528 ****
--- 1526,1532 ----
          Quotes are added only if necessary (i.e., if the string contains
          non-identifier characters or would be case-folded).
          Embedded quotes are properly doubled.
+         See also <xref linkend="plpgsql-quote-literal-example">.
         </entry>
         <entry><literal>quote_ident('Foo bar')</literal></entry>
         <entry><literal>"Foo bar"</literal></entry>
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*** 1535,1540 ****
--- 1539,1548 ----
          Return the given string suitably quoted to be used as a string literal
          in an <acronym>SQL</acronym> statement string.
          Embedded single-quotes and backslashes are properly doubled.
+         Note that <function>quote_literal</function> returns null on null
+         input; if the argument might be null,
+         <function>quote_nullable</function> is often more suitable.
+         See also <xref linkend="plpgsql-quote-literal-example">.
         </entry>
         <entry><literal>quote_literal('O\'Reilly')</literal></entry>
         <entry><literal>'O''Reilly'</literal></entry>
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*** 1551,1556 ****
--- 1559,1590 ----
         <entry><literal>'42.5'</literal></entry>
        </row>
  
+       <row>
+        <entry><literal><function>quote_nullable</function>(<parameter>string</parameter> <type>text</type>)</literal></entry>
+        <entry><type>text</type></entry>
+        <entry>
+         Return the given string suitably quoted to be used as a string literal
+         in an <acronym>SQL</acronym> statement string; or, if the argument
+         is null, return <literal>NULL</>.
+         Embedded single-quotes and backslashes are properly doubled.
+         See also <xref linkend="plpgsql-quote-literal-example">.
+        </entry>
+        <entry><literal>quote_nullable(NULL)</literal></entry>
+        <entry><literal>NULL</literal></entry>
+       </row>
+ 
+       <row>
+        <entry><literal><function>quote_nullable</function>(<parameter>value</parameter> <type>anyelement</type>)</literal></entry>
+        <entry><type>text</type></entry>
+        <entry>
+         Coerce the given value to text and then quote it as a literal;
+         or, if the argument is null, return <literal>NULL</>.
+         Embedded single-quotes and backslashes are properly doubled.
+        </entry>
+        <entry><literal>quote_nullable(42.5)</literal></entry>
+        <entry><literal>'42.5'</literal></entry>
+       </row>
+ 
        <row>
         <entry><literal><function>regexp_matches</function>(<parameter>string</parameter> <type>text</type>, <parameter>pattern</parameter> <type>text</type> [, <parameter>flags</parameter> <type>text</type>])</literal></entry>
         <entry><type>setof text[]</type></entry>