WEEKSINYEAR_ISO scalar function

Returns the number of weeks within the year that ADATE exists within, or the number of weeks in AYEAR according to the ISO8601 standard.

Prototypes

WEEKSINYEAR_ISO(AYEAR INTEGER)
WEEKSINYEAR_ISO(ADATE DATE)
WEEKSINYEAR_ISO(ADATE TIMESTAMP)
WEEKSINYEAR_ISO(ADATE VARCHAR(26))

RETURNS SMALLINT

Description

Returns the number of weeks in AYEAR according to the ISO8601 standard (weeks start on a Monday, and overlap calendar year ends to ensure all weeks are “whole”), or the number of weeks in the year that ADATE exists within depending on the variant of the function that is called.

Parameters

AYEAR
If provided, the year for which to calculate the number of weeks.
ADATE
If provided, the date in the year for which to calculate the number of weeks. Either AYEAR or ADATE must be specified.

Examples

Calculate the number of weeks in the year 2010 according to ISO8601:

VALUES WEEKSINYEAR_ISO(2010);

1
------
    52

Calculate the number of weeks in the first 10 years of the 21st century according to ISO8601:

SELECT YEAR(D) AS YEAR, WEEKSINYEAR_ISO(D) AS WEEKS
FROM TABLE(DATE_RANGE('2000-01-01', '2010-01-01', 10000));

YEAR        WEEKS
----------- ------
       2000     52
       2001     52
       2002     52
       2003     52
       2004     53
       2005     52
       2006     52
       2007     52
       2008     52
       2009     53
       2010     52

See Also