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Development Tools Database Foundations Manipulating Schema with SQL Altering Tables

Sean Flanagan
Sean Flanagan
33,235 Points
Posted by 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
229,783 Points
Steven Parker
Steven Parker
229,783 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.