UPDATE — modify existing rows.
Syntax:
1-- Update single column2UPDATE customers3SET email = 'newemail@example.com'4WHERE id = 123;56-- Update multiple columns7UPDATE orders8SET status = 'shipped', shipped_date = CURRENT_DATE9WHERE order_id = 456;1011-- Update with condition12UPDATE products13SET price = price * 1.114WHERE category = 'Electronics';
Warning: Always use WHERE clause!
1-- DANGER: Updates ALL rows2UPDATE customers SET status = 'active';
BA relevance: Understand data changes, write requirements.