Re: XMLDocument (SQL/XML X030)

On 01/24/25 10:49, Chapman Flack wrote:
> The SQL-standard `XMLDOCUMENT` function applied to an XML value
> /expr/ has effects equivalent to the XML Query expression
> `document { /expr/ }`, specified to replace any document nodes
> in the input with their children and wrap the whole result in one
> document node. An XML Query "document node" is a relaxed version
> of XML document structure, which need not have exactly one child
> element node, and also allows text nodes as children.

Or even: ... An XML Query "document node" is a relaxed version
of XML document structure that corresponds exactly to what
PostgreSQL's one XML type is already allowed to contain, so
any non-null PostgreSQL XML value can be returned unchanged.
More-permissive XML types some systems offer may hold values
that are not so structured.

Regards,
-Chap