ALTER TABLE TARIFAS ADD TAR_RUT VARCHAR(3)
GO
CREATE TABLE COMISIONES ( 
COM_ID INT DEFAULT ((0)) NOT NULL,
COM_INI DECIMAL(14,4) DEFAULT ((0)) NOT NULL,
COM_FIN DECIMAL(14,4) DEFAULT ((0)) NOT NULL,
COM_COD VARCHAR(3) NOT NULL
 CONSTRAINT PK_COMISIONES PRIMARY KEY CLUSTERED (COM_ID),
 CONSTRAINT CK_COMISIONESCOM_COD CHECK ((len([COM_COD])>(0))))
GO