Removing rows with DELETE

DELETE removes the rows that match a WHERE condition:

DELETE FROM product WHERE code = 'P03';

Only the matching rows are removed; the table and its other rows stay.

The same warning

Like UPDATE, a DELETE with no WHERE hits every row:

DELETE FROM product;   -- empties the whole table!

Always check your WHERE before running a DELETE. The checker runs your DELETE, then reads the table back to confirm the right row is gone.

Common mistakes

• DELETE without a WHERE empties the table — always add the WHERE.
• Test a risky delete first as a SELECT with the same WHERE.