Generate XML code from SQL Select

[Coach]

I want to know if this statement is valid to generate XML code:select xmlgen.getXml('select aircraftsuspensionid, missionid, projectid, suspensionid, suspensionnamefrom aircraftsuspensionwhere aircraftsuspensionid = 22') from dual;I get the following error when I execute the above statement:ERROR at line 1:ORA-00904: "XMLGEN"."GETXML": invalid identifier