MySQL DAYOFWEEK() Function

In MySQL, the DAYOFWEEK() function returns the weekday index of a given date.

DAYOFWEEK() Syntax

Here is the syntax of MySQL DAYOFWEEK() function:

DAYOFWEEK(expr)

Parameters

expr
Required. A date or datetime expression.

Return value

The MySQL DAYOFWEEK() function returns the weekday index of a given date. It returns a number 1 from to 7, representing the weekday names as following:

  • 1 - Sunday
  • 2 - Monday
  • 3 - Tuesday
  • 4 - Wednesday
  • 5 - Thursday
  • 6 - Friday
  • 7 - Saturday

If the specified expression is not a valid date or datetime, the DAYOFWEEK() function will return NULL.

If the argument is NULL, the DAYOFWEEK() function will return NULL.

DAYOFWEEK() Examples

Here are some examples of the DAYOFWEEK() function.

SELECT
    DAYOFWEEK('2022-02-21'),
    DAYOFWEEK('2022-02-22'),
    DAYOFWEEK('2022-02-23'),
    DAYOFWEEK('2022-02-24'),
    DAYOFWEEK('2022-02-25'),
    DAYOFWEEK('2022-02-26'),
    DAYOFWEEK('2022-02-27'),
    DAYOFWEEK('2022-02-00'),
    DAYOFWEEK('2022-02-30'),
    DAYOFWEEK('Not A DATE'),
    DAYOFWEEK(NULL)\G

DAYOFWEEK('2022-02-21'): 2
DAYOFWEEK('2022-02-22'): 3
DAYOFWEEK('2022-02-23'): 4
DAYOFWEEK('2022-02-24'): 5
DAYOFWEEK('2022-02-25'): 6
DAYOFWEEK('2022-02-26'): 7
DAYOFWEEK('2022-02-27'): 1
DAYOFWEEK('2022-02-00'): NULL
DAYOFWEEK('2022-02-30'): NULL
DAYOFWEEK('Not A DATE'): NULL
        DAYOFWEEK(NULL): NULL