How to get the number of days of difference between two dates on mysql?

Note if you want to count FULL 24h days between 2 dates, datediff can return wrong values for you.

As documentation states:

Only the date parts of the values are used in the calculation.

which results in

select datediff('2016-04-14 11:59:00', '2016-04-13 12:00:00')

returns 1 instead of expected 0.

Solution is using select timestampdiff(DAY, '2016-04-13 11:00:01', '2016-04-14 11:00:00'); (note the opposite order of arguments compared to datediff).

Some examples:

• select timestampdiff(DAY, '2016-04-13 11:00:01', '2016-04-14 11:00:00'); returns 0
• select timestampdiff(DAY, '2016-04-13 11:00:00', '2016-04-14 11:00:00'); returns 1
• select timestampdiff(DAY, '2016-04-13 11:00:00', now()); returns how many full 24h days has passed since 2016-04-13 11:00:00 until now.

Hope it will help someone, because at first it isn't much obvious why datediff returns values which seems to be unexpected or wrong.

I prefer TIMESTAMPDIFF because you can easily change the unit if need be.

What about the DATEDIFF function ?

Quoting the manual's page :

DATEDIFF() returns expr1 – expr2 expressed as a value in days from one date to the other. expr1 and expr2 are date or date-and-time expressions. Only the date parts of the values are used in the calculation

In your case, you'd use :

mysql> select datediff('2010-04-15', '2010-04-12');
+--------------------------------------+
| datediff('2010-04-15', '2010-04-12') |
+--------------------------------------+
|                                    3 | 
+--------------------------------------+
1 row in set (0,00 sec)

But note the dates should be written as YYYY-MM-DD, and not DD-MM-YYYY like you posted.

Use the DATEDIFF() function.

Example from documentation:

SELECT DATEDIFF('2007-12-31 23:59:59','2007-12-30');
    -> 1