연산자# 날짜 + 정수select date '2020-07-15' + integer '7' as result; ㅡ> 2020-07-22# 날짜 + 시간select date '2020-07-15' + time '13:00' as result; ㅡ> 2020-07-15 13:00:00# 날짜 - 날짜select date '2020-07-15' - date '2020-07-01' as result; ㅡ> 14# 시간 - 시간select time '13:00' - time '5:00' as result; ㅡ> 08:00:00 (INTERVAL 데이터 타입)# 정수 * 시간 간격(INTERVAL)select 60 * interval '1 second' as result; ㅡ> 00:01:00# 시간 간..