YEARWEEK(): function in a MySQL date and time field
Returns the year & week from a date .
Syntax
YEARWEEK(date,[mode])
Example
SELECT YEARWEEK('2016-09-23')
Output is 201638
For a invalid date we will get Null as output
SELECT YEAR('2010-02-31')
Output is NULL
Understanding Mode (Optional Parameter , value 0 to 7)
The week can start on Sunday or Monday,
To understand uses of MODE, read WEEK() function
If mode is not given, then it is considered as 0. The default_week_format of the MySQL system variables is not considered in YEARWEEK() function like WEEK() function. This is the main difference while using MODE between WEEK() function and YEARWEEK() function.
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