The following code:
SELECT xml-addressdb ASSIGN 'address.xml' ORGANIZATION IS XML DOCUMENT-TYPE IS OMITTED FILE STATUS xml-status.
Is equivalent to:
SELECT xml-addressdb ASSIGN 'address.xml' ORGANIZATION IS XML FILE STATUS xml-status.
SELECT foobar ASSIGN TO "foobar.xml" ORGANIZATION IS XML DOCUMENT TYPE IS "foobar.xsd" CHECK VALIDITY ON INPUT CHECK OUTPUT.