SQLCODE +1 while rehosting

I am getting a SQLcode of +1 in my query which is given below. I have to find the reason of the warning. Any help?

EXEC SQL
SELECT
DATEDIFF(d,getdate(),DUE_DATE)
,getdate(),DUE_DATE
INTO :WS-DATE-DIFFERENCE,
:WS-RETURN-DATE,:WS-DUE-DATE
FROM LIB_TRANSACT
WHERE MEM_ID=:WS-MEMID AND BOOK_ID=:WS-BOOKID
AND RETURN_DATE IS NULL
END-EXEC

This is the query.

Arun Kumar,
BAngalore