INSERT dan UPDATE dalam satu query MYSQL

Jika Anda menggunakan pendekatan pemicu maka Anda memerlukan dua pemicu (untuk menyisipkan dan menghapus)

CREATE TRIGGER tg_ai_orders
AFTER INSERT ON orders
FOR EACH ROW
  UPDATE bands 
     SET stock = stock - 1
   WHERE band_id = NEW.band_id;

CREATE TRIGGER tg_ad_orders
AFTER DELETE ON orders
FOR EACH ROW
  UPDATE bands 
     SET stock = stock + 1
   WHERE band_id = OLD.band_id;

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