-- create a table
CREATE TABLE classi (
  idclasse TEXT PRIMARY KEY,
  sede TEXT NOT NULL,
  piano INT NOT NULL,
  aula INT NOT NULL,
  codclasse CHAR(4) REFERENCES classi(codclasse) 
);

  INSERT INTO classi
  (idclasse,sede,piano,aula,codclasse)
  VALUES('D','viale europa',5,40,'M001');