Shift rota added to SQL script

It would help if you could include code and what you expect to see. You can do a sequence to cycle:

DROP SEQUENCE IF EXISTS dbo.fred;

CREATE SEQUENCE dbo.fred
AS TINYINT
START WITH 1
INCREMENT BY 1
MINVALUE 1
MAXVALUE 14
CYCLE
NO CACHE;

DECLARE @i INT = 0
WHILE @i < 100
BEGIN
SELECT NEXT VALUE FOR dbo.fred;

SET @i = @i + 1;
END;

If "date calendar " is a table with dates, just update that table with the shifts you want it to have (that will also give you the ability to override values later too. 

If I am off base, provide some data structures and what the output should be and someone might be able to help