After further research the answer is below. This will work in a passthrough query, querying an Oracle database.
Very useful.
Cheers
Ian
SELECT
TO_DATE('2010-01-01','YYYY-MM-DD') + ((LEVEL - 1) * 1) start_dt
, LEAST(TO_DATE('2010-01-01','YYYY-MM-DD') + ((LEVEL - 1) * 1) + 9
...