2018-03-09 0:10 GMT-03:00 PG Doc comments form <nore...@postgresql.org>:
> From testing, it seems like PostgreSQL supports the syntax "IS NOT DOCUMENT"
> in addition to "IS DOCUMENT", similar to "IS NOT NULL", "IS NOT FALSE", etc,
> however this does not appear to be documented, only "IS DOCUMENT" is.
>
It has been like that since day 1. I'm not sure why it was not
documented. It already has some tests. I'll bet that was an oversight.
Should we repeat the statement in another item (like the attached
patch)? Another option is to add a statement in the "IS DOCUMENT"
item. I'm afraid that NULL return wouldn't be clear.
--
Euler Taveira Timbira -
http://www.timbira.com.br/
PostgreSQL: Consultoria, Desenvolvimento, Suporte 24x7 e Treinamento
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 2f59af2..fcef246 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -10399,6 +10399,24 @@ SELECT xmlagg(x) FROM (SELECT * FROM test ORDER BY y DESC) AS tab;
</para>
</sect3>
+ <sect3>
+ <title><literal>IS NOT DOCUMENT</literal></title>
+
+ <indexterm>
+ <primary>IS NOT DOCUMENT</primary>
+ </indexterm>
+
+<synopsis>
+<replaceable>xml</replaceable> IS NOT DOCUMENT
+</synopsis>
+
+ <para>
+ The expression <literal>IS NOT DOCUMENT</literal> returns false if the
+ argument XML value is a proper XML document, true if it is not (that is,
+ it is a content fragment), or null if the argument is null.
+ </para>
+ </sect3>
+
<sect3 id="xml-exists">
<title><literal>XMLEXISTS</literal></title>
