xpath_number function

Returns a DOUBLE value from an XML document.

Syntax

xpath_number(xml, xpath)

Arguments

  • xml: A STRING expression of XML.

  • xpath: A STRING expression that is a well formed XPath.

Returns

A DOUBLE.

The result is zero if no match is found, or NaN if a match is found but the value is non-numeric.

The function raises an error if xml or xpath are malformed.

Examples

> SELECT xpath_number('<a><b>1</b><b>2</b></a>', 'sum(a/b)');
 3.0