Case statement for Order By clause with Desc/Asc sort

Question

SELECT *
FROM
    TableName
WHERE
ORDER BY 
    CASE @OrderByColumn
    WHEN 1 THEN Forename
    WHEN 2 THEN Surname
    END;

I have a statement like a

Answer 1

You need to split your ORDER BY in two parts:

SELECT *
FROM
    TableName
WHERE
ORDER BY 
    (CASE @OrderByColumn
    WHEN 1 THEN Forename
    END) DESC -- Forename --> descending
,   (CASE @OrderByColumn
    WHEN 2 THEN Surname
    END) ASC -- Surname --> ascending