EXTRACTVALUE

Purpose

EXTRACTVALUE() extracts a value from an XML string using XPath notation.

Syntax

EXTRACTVALUE(xml_frag, xpath_expr)

Parameters

Return type

The return type is LONGTEXT.

Examples

• Multiple matched results are separated by spaces.

  Call the EXTRACTVALUE() function to extract values from the given XML string <a><b>x</b><b>y</b></a> on the XPath /a/b.

  obclient [test_db]> SELECT EXTRACTVALUE('<a><b>x</b><b>y</b></a>', '/a/b');
  

  The return result is as follows:

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

• An empty string is returned when no matched results are found.

  obclient [test_db]> SELECT EXTRACTVALUE('<a><b>x</b><b>y</b></a>', '/a/c');
  

  The return result is as follows:

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