Apakah MySQL mengizinkan panggilan balik dalam C sehingga ketika terjadi perubahan, saya dapat diberi tahu?

Buat pemicu seperti itu.

DELIMITER $$

CREATE TRIGGER ad_mytable_each AFTER DELETE ON MyTable FOR EACH ROW
BEGIN
  #write code that trigger After delete (hence the "ad_" prefix)
  #For table MyTable (The _MyTable_ middle)
  #On each row that gets inserted (_each suffix)
  #
  #You can see the old delete values by accesing the "old" virtual table.
  INSERT INTO log VALUES (old.id, 'MyTable', old.field1, old.field2, now());

END$$

DELIMITER ;

Ada pemicu untuk INSERT , DELETE , UPDATE
Dan mereka dapat menembakkan BEFORE atau AFTER tindakan.
Pemicu BEFORE tindakan dapat membatalkan tindakan dengan memaksa kesalahan, seperti itu.

CREATE TRIGGER bd_mytable_each BEFORE DELETE ON MyTable FOR EACH ROW
BEGIN
  #write code that trigger Before delete (hence the "db_" prefix)
  declare DoError Boolean; 

  SET DoError = 0;

  IF old.id = 1 THEN SET DoError = 1; END IF; 

  IF (DoError = 1) THEN SELECT * FROM Table_that_does_not_exist_to_force_error;
  #seriously this example is in the manual.

END$$

DELIMITER ;

Ini akan mencegah penghapusan catatan 1.

A sebelum UPDATE Trigger bahkan dapat mengubah nilai yang diperbarui.

CREATE TRIGGER bu_mytable_each BEFORE UPDATE ON MyTable FOR EACH ROW
BEGIN
  IF new.text = 'Doon sucks' THEN SET new.text = 'Doon rules';
END$$

DELIMITER ;

Semoga Anda menjadi Trigger bahagia.