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Development Tools Database Foundations Manipulating Schema with SQL Altering Tables

Sean Flanagan
Sean Flanagan
33,235 Points

DELETE vs DROP vs TRUNCATE

Hi.

So have I got this right? DELETE deletes one table row, TRUNCATE deletes every row in a table, and DROP deletes the entire table?

Thanks in advance.

Sean

1 Answer

Steven Parker
Steven Parker
231,172 Points

Close. You're right about TRUNCATE and DROP. Now DELETE can remove a single row, it can also delete every row. For example:

DELETE FROM mytable WHERE id = 21;

...would remove just one row (assuming id is a unique key and there is a row with 21 in it). But just this:

DELETE FROM mytable;

...would remove every row. By using different WHERE conditions you could also delete more than one, but not all rows.