MySQL - Setelah Delete Trigger

Halo sana, para entusiastik basis data yang sedang berkembang! Hari ini, kita akan masuk ke dalam dunia yang menarik dari MySQL triggers, khususnya trigger After Delete. Sebagai guru ilmu komputer yang ramah di lingkungan sekitar Anda, saya sangat gembira untuk memandu Anda dalam perjalanan ini. Jangan khawatir jika Anda baru belajar pemrograman – kita akan mulai dari dasar dan kemudian naik tingkat. Jadi, ambil secangkir kopi (atau teh, jika itu hal Anda), dan mari kita mulai!

Apa Itu MySQL Trigger?

Sebelum kita melompat ke trigger After Delete, mari kita pahami apa itu trigger di MySQL. Bayangkan Anda memiliki anjing setia yang selalu menggonggong saat seseorang menggoyangkan bel. Dalam analogi ini, bel adalah suatu peristiwa, dan gonggongan anjing adalah tanggapan otomatis terhadap peristiwa itu. Demikian pula, di MySQL, trigger adalah tanggapan otomatis terhadap suatu peristiwa khusus dalam basis data.

MySQL After Delete Trigger

Sekarang, mari fokuskan diri kita pada bintang hari ini – trigger After Delete. Seperti yang diindikasikan namanya, trigger ini akan terbakar setelah operasi DELETE terjadi pada suatu tabel. Itu seperti memiliki tim pembersihan yang datang setelah pesta untuk memastikan bahwa semua halus.

Sintaks After Delete Trigger

Berikut adalah sintaks dasar untuk membuat trigger After Delete:

CREATE TRIGGER trigger_name
AFTER DELETE ON table_name
FOR EACH ROW
BEGIN
-- Tubuh Trigger
END;

Marilah kitauraikan ini:

1. CREATE TRIGGER trigger_name: Ini adalah tempat Anda memberi nama trigger Anda.
2. AFTER DELETE ON table_name: Ini menentukan bahwa trigger harus terbakar setelah operasi DELETE pada tabel yang ditentukan.
3. FOR EACH ROW: Ini berarti trigger akan dieksekusi sekali untuk setiap baris yang terkena dampak oleh operasi DELETE.
4. BEGIN dan END: Kata-kata kunci ini menyelubungi tubuh trigger, tempat Anda menentukan tindakan apa yang harus diambil.

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