UPDATE dengan FROM dan Pembaruan Bergaya JOIN

UPDATE Dasar

UPDATE users SET full_name = 'Alice Adams' WHERE id = 1;

Beberapa Kolom

UPDATE users
SET full_name = 'Alice', last_login = NOW(), visits = visits + 1
WHERE id = 1;

Memperbarui Banyak Baris

UPDATE orders SET status = 'archived'
WHERE created_at < NOW() - INTERVAL '5 years';

UPDATE dengan Subkueri

UPDATE products
SET review_count = (
  SELECT COUNT(*) FROM reviews WHERE reviews.product_id = products.id
);

UPDATE … FROM (PostgreSQL)

UPDATE products p
SET stock = i.qty
FROM inventory i
WHERE i.product_id = p.id;

UPDATE … FROM dengan Beberapa Tabel

UPDATE invoices inv
SET tax_rate = r.rate
FROM users u
JOIN rates r ON r.country = u.country
WHERE inv.user_id = u.id;

SQL Standar: UPDATE … FROM melalui Subkueri Berkorelasi

UPDATE products p
SET stock = (SELECT qty FROM inventory i WHERE i.product_id = p.id);

MERGE untuk INSERT/UPDATE/DELETE

RETURNING dari UPDATE

UPDATE orders SET status = 'shipped', shipped_at = NOW()
WHERE id = $1
RETURNING id, status, shipped_at;

Memperbarui dengan CASE

UPDATE orders
SET status = CASE
  WHEN paid_at IS NOT NULL THEN 'paid'
  WHEN created_at < NOW() - INTERVAL '24h' THEN 'expired'
  ELSE status
END;

Waspadai WHERE yang Hilang

Performa UPDATE

Ringkasan

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