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 two clauses in the order by:

ORDER BY (CASE WHEN @OrderByColumn = 1 and @Dir = 'ASC' THEN Forename
               WHEN @OrderByColumn = 2 and @Dir = 'ASC' THEN Surname
          END) ASC,
         (CASE WHEN @OrderByColumn = 1 and @Dir = 'DESC' THEN Forename
               WHEN @OrderByColumn = 2 and @Dir = 'DESC' THEN Surname
          END) DESC