TRUNCATE [ TABLE ] name
TRUNCATE quickly removes all rows from a table. It has the same effect as an unqualified DELETE but since it does not actually scan the table it is faster. This is most useful on large tables.
TRUNCATE cannot be executed inside a transaction block (BEGIN/COMMIT pair), because there is no way to roll it back.
Truncate doesn't call any triggers on the table as it removes data, so if you want your triggers called you have to do a delete.