In MariaDB, DAYOFWEEK() is a built-in date and time function that returns the day of the week from a given date.
It accepts one argument, which is the date you want to extract the day of the week from.
It returns the day as a number. The index numbering adheres to the ODBC standard (1 = Sunday, 2 = Monday, etc). This is in contrast to WEEKDAY(), where 0 = Monday, 1 = Tuesday, etc.