UNION Tips

SELECT BATCH_NUMBER,FULL_NAME,LEAVE_TYPE
,DECODE(LEAVE_TYPE,'Casual',12,'Special',15,'Medical',10,'Unpaid Leave',SUM(NO_OF_DAYS)) TOTAL_DAYS
,SUM(NO_OF_DAYS) LEAVE_DAYS,
(DECODE(LEAVE_TYPE,'Casual',12,'Special',15,'Medical',10))-(SUM(NO_OF_DAYS)) available
FROM XXMPCD_AT_LEAVE_TYPE_DTLS WHERE FULL_NAME='RajaShekar'
GROUP BY BATCH_NUMBER,FULL_NAME,LEAVE_TYPE
UNION
SELECT NULL,NULL,
LOOKUP_CODE,(SELECT DECODE(LOOKUP_CODE,'Casual',12,'Special',15,'Medical',10) FROM
DUAL ) TOTAL_DAYS, 0 LEAVE_DAYS,(SELECT DECODE(LOOKUP_CODE,'Casual',12,'Special',15,'Medical',10) FROM
DUAL ) available FROM FND_LOOKUP_VALUES WHERE LOOKUP_TYPE='XXMPCD_LEAVE_TYPE' AND ENABLED_FLAG='Y' AND END_DATE_ACTIVE IS NULL
AND LOOKUP_CODE NOT IN  (
SELECT LEAVE_TYPE
FROM XXMPCD_AT_LEAVE_TYPE_DTLS WHERE FULL_NAME='RajaShekar'
GROUP BY BATCH_NUMBER,FULL_NAME,LEAVE_TYPE);