The full query in Toad included "order by rowid desc nulls last;" so I tried the last create table with "order by sy_history_ID desc" and it worked fine. So, I tried "order by sy_History_ID desc nulls last;" and then the query failed in the oracle sql command window.
ORA-04036: PGA memory used by the instance exceeds PGA_AGGREGATE_LIMIT
ORA-06512 at "SYS.XMLTYPE", line 138
Joe