What is ISO_year in sql-server

Question

I am currently working on creating my first Data_warehouse using sql-server

I have a Date dimension i want to populate it using SSIS it ha

Answer 1

Here is a function for iso_year, the logic behind it is that the thursday of the week from the parameter date determine the year:

CREATE FUNCTION [dbo].[f_isoyear]
(
@p_date datetime
)
RETURNS int
as
BEGIN
  RETURN datepart(yy, dateadd(wk, datediff(d, 0, @p_date)/7, 3))
END

Answer 2

Here is a Connect item that requests a function to calculate ISO_YEAR.

DATEPART - ISO_YEAR for ISO_WEEK

In the workaround section you have this function that you can use.

CREATE FUNCTION [dbo].[ISOyear](@date DATETIME)
returns SMALLINT
AS
BEGIN
     DECLARE @isoyear SMALLINT = CASE
         WHEN Datepart(isowk, @date)=1
             AND Month(@date)=12 THEN Year(@date)+1
         WHEN Datepart(isowk, @date)=53
             AND Month(@date)=1 THEN Year(@date)-1
         WHEN Datepart(isowk, @date)=52
             AND Month(@date)=1 THEN Year(@date)-1             
         ELSE Year(@date)
        END;
     RETURN @isoyear;
END;