CREATE TABLE facturacion(
    fecha DATE NULL,
    venta_total FLOAT
);

DELIMITER //
CREATE TRIGGER tg_facturacion_insert
AFTER INSERT ON items
FOR EACH ROW BEGIN
  DELETE FROM facturacion;
  INSERT INTO facturacion
  SELECT A.FECHA, SUM(B.cantidad * B.precio) AS VENTA_TOTAL
  FROM facturas A
  INNER JOIN
  items B
  ON A.NUMERO = B.NUMERO
  GROUP BY A.FECHA;
END //

DELIMITER //
CREATE TRIGGER tg_facturacion_delete
AFTER DELETE ON items
FOR EACH ROW BEGIN
  DELETE FROM facturacion;
  INSERT INTO facturacion
  SELECT A.fecha, SUM(B.cantidad * B.precio) AS VENTA_TOTAL
  FROM facturas A
  INNER JOIN
  items B
  ON A.numero = B.numero
  GROUP BY A.fecha;
END //

DELIMITER //
CREATE TRIGGER tg_facturacion_update
AFTER UPDATE ON items
FOR EACH ROW BEGIN
  DELETE FROM facturacion;
  INSERT INTO facturacion
  SELECT A.fecha, SUM(B.cantidad * B.precio) AS VENTA_TOTAL
  FROM facturas A
  INNER JOIN
  items B
  ON A.numero = B.numero
  GROUP BY A.fecha;
END //

DELIMITER ;