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
