如何添加日期时间和时间

In my database table, I am storing current date and time using NOW() function. The column type is DATETIME and it is storing in the format of YYYY-MM-DD HH:MM:SS.

I am trying to write a query that selects the date and time from my table column and adding HH:MM to retrieved date and time like

SELECT date FROM tablename by adding fetched date which is (YYYY-MM-DD HH:MM:SS) + HH:MM

The above query is just to make you know what I was trying.

Actually I don't know how to add date and time in mysql while retrieving the data.

How can we add YYYY-MM-DD HH:MM:SS and HH:MM while retrieving the data in mysql.

You can use ADDTIME in MySQL:

SELECT ADDTIME('2016-07-15 18:00:00', '02:30');

or with DATEADD

SELECT DATE_ADD('2016-07-15 18:00:00', INTERVAL '02:30' HOUR_MINUTE);

Both Result as:

2016-07-15 20:30:00

you don't do anything special:

SELECT ... WHERE datetimefield = '2016-07-15 13:13:00'

mysql will parse the string to see if it looks like a valid date/datetime value and convert it for you automatically.

For date "math", you can do that directly as well:

mysql> select '2016-07-16 13:13:00' + INTERVAL 3 hour + INTERVAL 15 minute;
+--------------------------------------------------------------+
| '2016-07-16 13:13:00' + INTERVAL 3 hour + INTERVAL 15 minute |
+--------------------------------------------------------------+
| 2016-07-16 16:28:00                                          |
+--------------------------------------------------------------+
1 row in set (0.00 sec)