When you need to delete data from a table in the database, you can use a
DELETE statement, which
describes the table to act on, and the rows of the table to delete through the
DELETE FROM mytable WHERE condition;
If you decide to leave out the
WHERE constraint, then all rows are removed, which is a quick
and easy way to clear out a table completely (if intentional).
UPDATE statement from last lesson, it's recommended that you run the constraint in a
SELECT query first to ensure that you are removing the right rows. Without a proper backup or test
database, it is downright easy to irrevocably remove data, so always read your
twice and execute once.
The database needs to be cleaned up a little bit, so try and delete a few rows in the tasks below.