Declanşator pentru ştergere în cascadă (echivalent cu ON DELETE CASCADE):
CREATE TABLE Localitate
(
CodLocalitate INT PRIMARY KEY,
Denumire VARCHAR(25) NOT NULL
)
GO

CREATE TABLE Telefon
(
NrTelefon VARCHAR(25) PRIMARY KEY NOT NULL,
CodLocalitate INT NOT NULL
REFERENCES Localitate(CodLocalitate)
--ON DELETE CASCADE --fara stergere in cascada
)
GO

INSERT INTO Localitate VALUES (1,'Bucuresti')
INSERT INTO Localitate VALUES (2,'Ploiesti')
GO
INSERT INTO Telefon VALUES ('3123219',1)
INSERT INTO Telefon VALUES ('4569567',1)
INSERT INTO Telefon VALUES ('8796674',1)
INSERT INTO Telefon VALUES ('111111',2)
INSERT INTO Telefon VALUES ('222222',2)
GO

CREATE TRIGGER StergereLocalitate
ON Localitate
INSTEAD OF DELETE
AS
  DELETE Telefon
  FROM Telefon INNER JOIN DELETED ON Telefon.CodLocalitate = DELETED.CodLocalitate

  DELETE FROM Localitate
  FROM Localitate INNER JOIN DELETED ON Localitate.CodLocalitate = DELETED.CodLocalitate
GO

--5 inregistrari
SELECT * FROM Telefon
GO

DELETE FROM Localitate WHERE Denumire = 'Ploiesti'
GO

--3 inregistrari
SELECT * FROM Telefon
GO