What's the best way to select the minimum value from several columns?

Question

Given the following table in SQL Server 2005:

ID   Col1   Col2   Col3
--   ----   ----   ----
1       3     34     76  
2      32    976     24
3       7             


        

Answer 1

If the columns were integers as in your example I would create a function:

create function f_min_int(@a as int, @b as int) 
returns int
as
begin
    return case when @a < @b then @a else coalesce(@b,@a) end
end

then when I need to use it I would do :

select col1, col2, col3, dbo.f_min_int(dbo.f_min_int(col1,col2),col3)

if you have 5 colums then the above becomes

select col1, col2, col3, col4, col5,
dbo.f_min_int(dbo.f_min_int(dbo.f_min_int(dbo.f_min_int(col1,col2),col3),col4),col5)