XML Functions +-------------------------------------+ | 0 | +-------------------------------------+ 1 row in set (0.01 sec) Important ExtractValue()  returns only  CDATA , and does not return any tags that might be contained within a matching tag, nor any of their content (see the result returned as  val1  in the following example). This function uses the current SQL collation for making comparisons with  contains() , performing the same collation aggregation as other string functions (such as  CONCAT() ), in taking into account the collation coercibility of their arguments; see Section 10.8.4, “Collation Coercibility in Expressions” , for an explanation of the rules governing this behavior. (Previously, binary—that is, case-sensitive—comparison was always used.) NULL  is returned if  xml_frag  contains elements which are not properly nested or closed, and a warning is generated, as shown in this example: 2250 mysql>  SELECT ExtractValue(’<a>c</a><b’, ’//a’); +-----------------------------------+ | ExtractValue(’<a>c</a><b’, ’//a’) | +-----------------------------------+ | NULL | +-----------------------------------+ 1 row in set, 1 warning (0.00 sec) mysql>  SHOW WARNINGS\G *************************** 1. row *************************** Level: Warning Code: 1525 Message: Incorrect XML value: ’parse error at line 1 pos 11: END-OF-INPUT unexpected (’>’ wanted)’ 1 row in set (0.00 sec) mysql>  SELECT ExtractValue(’<a>c</a><b/>’, ’//a’); +-------------------------------------+ | ExtractValue(’<a>c</a><b/>’, ’//a’) | +-------------------------------------+ | c | +-------------------------------------+ 1 row in set (0.00 sec) mysql>  SELECT ->  ExtractValue(’<a>ccc<b>ddd</b></a>’, ’/a’) AS val1, ->  ExtractValue(’<a>ccc<b>ddd</b></a>’, ’/a/b’) AS val2, ->  ExtractValue(’<a>ccc<b>ddd</b></a>’, ’//b’) AS val3, ->  ExtractValue(’<a>ccc<b>ddd</b></a>’, ’/b’) AS val4, ->  ExtractValue(’<a>ccc<b>ddd</b><b>eee</b></a>’, ’//b’) AS val5; +------+------+------+------+---------+ | val1 | val2 | val3 | val4 | val5 | +------+------+------+------+---------+ | ccc | ddd | ddd | | ddd eee | +------+------+------+------+---------+