DAYOFWEEK(date) returns the day of the week for a given date, starting with 1=Sunday, 2=Monday, 3=Tuesday, and so on. : DAYOFWEEK « Date Time Functions « MySQL Tutorial

1. MySQL Tutorial
2. Date Time Functions
3. DAYOFWEEK

mysql>
mysql> SELECT DAYOFWEEK('0-2-1');
+--------------------+
| DAYOFWEEK('0-2-1') |
+--------------------+
|                  3 |
+--------------------+
1 row in set (0.00 sec)

mysql>