DELETE and safe targeting
DELETE removes records. A selective condition and a verification query keep that change deliberate.
Preview the rows
Use SELECT with the intended WHERE condition to inspect the records you plan to remove. DELETE removes whole rows rather than individual column values.
Delete a subset
DELETE FROM table_name WHERE condition removes matching records. Omitting WHERE targets the whole table. The lab is disposable, but use deliberate targeting as a habit.
Relationships and protection
Foreign-key rules can reject a deletion that would leave dependent rows orphaned. Do not disable integrity rules merely to make a deletion succeed.
Verify the remaining data
Check both that the intended rows are gone and that other records remain. A transaction lets you roll back a change before committing it in a real database.