Prueba cambiando el formato de las referencias:
create table
compras_lin
(id int auto_increment primary key,
NCompra int not null default 1,
Articulo int(6) not null default 1,
Descipcion char(20) default '',
Cantidad double(8,2) default 1.00,
Precio double (9,2) default 0.00,
Descuento float(4,1) default 0.0,
Tipo_IVA tinyint(3) not null default 1,
Neto double(9,2) default 0.00,
CONSTRAINT `NCompra_id` FOREIGN KEY (`NCompra`) REFERENCES `compras_cab` (`id`) ON UPDATE CASCADE,
CONSTRAINT `Articulo_id` FOREIGN KEY (`Articulo`) REFERENCES `articulos` (`id`) ON UPDATE CASCADE,
CONSTRAINT `Tipo_IVA_id` FOREIGN KEY (`Tipo_IVA`) REFERENCES `tipos_iva` (`id`) ON UPDATE CASCADE)
ENGINE=InnoDB
DEFAULT CHARACTER SET=utf8;
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Ing. Jesús Alfredo Uzcanga
Twitter: @JesusUzcanga
We learn the 20% of what we HEAR,
the 50% of what we SEE,
the 80% of what we DO and
the 95% of what we TEACH.
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