Menangani kesalahan

Transaksi dan Penanganan Error di PostgreSQL

Jason Myers

Principal Engineer

Kesalahan bisa terjadi

Tidak sengaja memperbarui Biscuits

UPDATE cookies SET quantity = 13 WHERE name = 'Biscuits';

Dikoreksi untuk memperbarui Biscotti

UPDATE cookies SET quantity = 1 WHERE name = 'Biscuits';

UPDATE cookies SET quantity = 13 WHERE name = 'Biscotti';

Membatalkan kesalahan

BEGIN TRANSACTION

UPDATE cookies SET quantity = 13 WHERE name = 'Biscuits';

ROLLBACK;

SELECT quantity FROM cookies where name = 'Biscuits';

Rollback beberapa pernyataan

BEGIN TRANSACTION;

UPDATE cookies SET deliciousness = 111 where name = 'Cats Tongue';

UPDATE cookies SET deliciousness = 8 where name = 'Gingerbread';

ROLLBACK;

SELECT name, deliciousness FROM cookies where name in ('Cats Tongue', 'Gingerbread');

'Cats Tongue'  10
'Gingerbread'   9

Ayo berlatih!

Transaksi dan Penanganan Error di PostgreSQL