Ora-22950 when comparing XML

Question

Hi,
I want to compare two tables for differences using MINUS, but this does an implicit ORDER BY. So I get the error:
ORA-22950: cannot ORDER objects without MAP or ORDER method
Does anyone know how to get round this ? Convering to CLOB (col1.getclobval()) also doesn't work:
CREATE TABLE dunc1 (col1 XMLTYPE);
CREATE TABLE dunc2 (col1 XMLTYPE);
SELECT col1 FROM dunc1
MINUS
SELECT col1 FROM dunc2;
TIA, Duncan

Answer 1

Hi
I get the same error (ORA-22950: cannot ORDER objects without MAP or ORDER method) when I try to fetch values from individual nodes in xmltype column from 2 tables with a union.
select tbl1.xmlcol.extract('//abc/ns1:def','xmlns:ns1="http://xy.z.org/"').getStringVal() col1,
tbl1.xmlcol.extract('//abc/ns1:ghi/text()','xmlns:ns1="http://abc.def.org/"') as col2
from table1 tbl1
union
select tbl2.xmlcol.extract('//xyz/ns1:def','xmlns:ns1="http://xy.z.org/"').getStringVal() col1,
tbl2.xmlcol.extract('//xyz/ns1:ghi/text()','xmlns:ns1="http://abc.def.org/"') as col2
from table2 tbl2;
What am I doing wrong here?
Thx!