oracle convert run duration to number
-- Duration between 2 timestamps
SELECT (extract(DAY FROM TIME2 - TIME1) * 24 * 60 * 60)
+ (extract(HOUR FROM TIME2 - TIME1) * 60 * 60)
+ (extract(MINUTE FROM TIME2 - TIME1) * 60)
+ extract(SECOND FROM TIME2 - TIME1)
FROM DUAL;