INSERT INTO base1.dbo.PRESTAMOS
(idprestamo,idcliente,fecha, fechap1, fechav, duracion, interes, comision, monto, balance,idtipo, fecha_pago, 
 cuota,idpago)
SELECT CAST(RIGHT([Código Préstamo],8) AS INT) AS IDPRESTAMO,CAST(RIGHT(CodCliente,8) AS INT) AS IDCLIENTE,
FECHA,Inicio AS FECHAP1,Vence AS FECHAV,Cuotas AS DURACION,cast(Tasa as numeric(12,2))*12 AS INTERES,0 AS COMISION,
Monto,case when Balance>0 then monto else 0 end as balance,6 as idtipo,
convert(varchar(10),CONVERT(datetime,ultpago,105),111) AS FECHA_PAGO,[Monto Cuotas]AS Cuota,
IDPAGO=CASE WHEN periodopago='D' THEN 1 ELSE 
CASE WHEN periodopago='S' THEN 2 ELSE
CASE WHEN periodopago='Q' THEN 3 ELSE 4 END END END FROM Préstamo