Some questions:
(0) What are your DB2 version/release and platform OS?
(1) What do you mean by "corrupt"?
Did you received error message(s) something like "... package xxxx corrupted ..."?
If so, please copy and paste the message(s).
Or did you received incorrect result?
If so, please publish incorrect result and expected result.
(2) Why did you relate "corrupt SQL package" and "duplicate data"?
(3) What do you mean by "duplicate data"?
(4) and more...
- Where did you found the "duplicate data"?
- When did you realized the "duplicate data"?
- How did you know the "duplicate data"?
- so on...