WEEK(date[,mode])

MySQL 8.4

This function returns the week number for date. The two-argument form of WEEK() enables you to specify whether the week starts on Sunday or Monday and whether the return value should be in the range from 0 to 53 or from 1 to 53. If the mode argument is omitted, the value of the default_week_format system variable is used. See Section 7.1.8, “Server System Variables”. For a NULL date value, the function returns NULL.

Syntax

MYSQL

SELECT WEEK('2008-02-20');
7
SELECT WEEK('2008-02-20',0);
7
SELECT WEEK('2008-02-20',1);
8
SELECT WEEK('2008-12-31',1);
53

Examples

Example

The following table describes how the mode argument works.

MYSQL

SELECT WEEK('2008-02-20');
7
SELECT WEEK('2008-02-20',0);
7
SELECT WEEK('2008-02-20',1);
8
SELECT WEEK('2008-12-31',1);
53

Example 2

For mode values with a meaning of “with 4 or more days this year,” weeks are numbered according to ISO 8601:1988:

MYSQL

SELECT YEAR('2000-01-01'), WEEK('2000-01-01',0);
2000, 0

Example 3

If the week containing January 1 has 4 or more days in the new year, it is week 1.

MYSQL

SELECT WEEK('2000-01-01',2);
52

Example 4

Otherwise, it is the last week of the previous year, and the next week is week 1.

MYSQL

SELECT YEARWEEK('2000-01-01');
199952
SELECT MID(YEARWEEK('2000-01-01'),5,2);
'52'