MySQL in a Nutshell

Name

DAYOFMONTH( )

Synopsis

DAYOFMONTH(date)

This function returns the day of the month for the date given. It returns NULL if the day for the date is greater than 31. It will accept a date like 2005-02-31 as valid and will return 31. Future releases of MySQL will resolve this problem.

SELECT DAYOFMONTH('2005-03-01')
       AS 'Day of Month';
+---------------+
| Day of Month  |
+---------------+
|             1 |
+---------------+

This is more meaningful when you apply it to a date column where the date is unknown before entering the SQL statement.