Entrypoint addmonth compatible with UTF-8
Input TIMESTAMP date optionally time INTEGER month to add Output TIMESTAMP adds months to the timestamp
If parameter 2 is negative, months where subtract. TestSQL SELECT '01.03.2006 15:03:01' AS ISCORRECT, F_ADDMONTH('01.10.2005 15:03:01', 5) FROM RDB$DATABASE; SELECT '01.07.2005 15:03:01' AS ISCORRECT, F_ADDMONTH('01.10.2005 15:03:01', -3) FROM RDB$DATABASE; SELECT NULL AS ISCORRECT, F_ADDMONTH(NULL, NULL) FROM RDB$DATABASE;