Винаги можете да използвате дроб (за Oracle 1 =1 ден):
SELECT CURRENT_TIMESTAMP ,
CURRENT_TIMESTAMP + 200 *(1/24/60/60) AS addedTime
FROM dual;
<=>
SELECT CURRENT_TIMESTAMP + 200/86400 FROM dual
Демонстрация на DBFiddle
или:
SELECT CURRENT_TIMESTAMP + INTERVAL '200' SECOND FROM dual