Key/Value table with limiters
So you're going to pass in two optional parameters:


@host
@env


Example sql (to be put in a stored proc):

Select top 1 * from dbo.FilterTable ft
Where 
    ((@host is not null and ft.host = @host) or ft.host is null)
    And ((@env is not null and ft.environment = @env) or ft.environment is null)
Order by 
    Case
        When ft.host is not null and ft.environment is not null then 1
        When ft.host is not null then 2
        When ft.environment is not null then 3
        Else 4
    End asc