En SQL Server harías algo como:
Código SQL
[-]
Select F.Factura,
case when datediff(dd, F.FechaFactura, GetDate()) <30 then F.Monto else 0 end dias30,
case when datediff(dd, F.FechaFactura, getdate()) between 31 and 45 then F.Monto else 0 end dias45
case when datediff(dd, F.FechaFactura, getdate()) between 46 and 60 then F.Monto else 0 end dias60
...
...
From Facturas F
where ...