EXTRACTVALUE

Description

This function is used to extract the value of a specified path from an XML string.

Syntax

EXTRACTVALUE(xml_frag, xpath_expr)

Parameters

Parameter	Description
xml_frag	The XML string to extract the value from. It can be an XML document or a fragment.
xpath_expr	The XPath expression specifying the path of the value to extract.

Return Type

The return type is LONGTEXT.

Examples

• Multiple results are separated by spaces.

  Use the EXTRACTVALUE function to extract the value of a specific node from the given XML string <a><b>x</b><b>y</b></a>, where the node path is /a/b.

  SELECT EXTRACTVALUE('<a><b>x</b><b>y</b></a>', '/a/b');

  The result is as follows:

  +-------------------------------------------------+
  | EXTRACTVALUE('<a><b>x</b><b>y</b></a>', '/a/b') |
  +-------------------------------------------------+
  | x y                                             |
  +-------------------------------------------------+
  1 row in set (0.001 sec)

• If no results are found, an empty string is returned.

  SELECT EXTRACTVALUE('<a><b>x</b><b>y</b></a>', '/a/c');

  The result is as follows:

  +-------------------------------------------------+
  | EXTRACTVALUE('<a><b>x</b><b>y</b></a>', '/a/c') |
  +-------------------------------------------------+
  |                                                 |
  +-------------------------------------------------+
  1 row in set (0.001 sec)