This question has nothing to do with Oracle Text, so perhaps some moderator will move it from Text to SQL and PL/SQL.
You are probably looking for something like:
SELECT createdate, TransactionDtTm, id, objid
FROM TBL1, TBL2
where active =1
AND trunc (createdate- start_date) <= 0;
For a nice explanation of date differences and an Oracle PL/SQL DATEDIFF function by Tom Kyte, please click on the link below.