Oracle查询日期和时间

Question

I am trying to get data from a table where start_date is less than or equal to a particular date and time value:

SELECT * FROM Table1 WHERE START_DATE <= TO_DATE('2/21/2018 2:40:20 PM', 'MM/dd/yyyy hh:mm:ss tt')

The error I am getting is format code appears twice

I have tried different formats but still cannot get it right

Answer 1

You have two problems.

1) The format model for minutes is "mi", not "mm".

2) The format model for AM/PM is "AM", not "tt".

So,

TO_DATE('2/21/2018 2:40:20 PM', 'MM/dd/yyyy hh:mi:ss AM')

Or, easier,

TO_DATE('2/21/2018 14:40:20', 'MM/dd/yyyy hh24:mi:ss')

(ie, a 24-hour clock)