像這樣...
-
Select
employees.employee_id,
employees.first_name,
employees.last_name,
tests.name,
testlog.test_date,
tests.frequency,
SYSDATE - testlog.test_date DayTaken,
SYSDATE - testlog.test_date - tests.frequency DaysOverdue
From employees, tests, testlog
Where
employees.employee_id = testlog.employee_id
and testlog.test_id = tests.test_id
and SYSDATE - testlog.test_date > tests.frequency;
-
lk777 大大所說的 trunc 因該放在哪呀??