Is it possible to negate a where clause?
DELETE * FROM table WHERE id != 2;
You can do like this
DELETE FROM table WHERE id NOT IN ( 2 )
DELETE FROM table WHERE id <> 2
As @Frank Schmitt noted, you might want to be careful about the NULL values too. If you want to delete everything which is not
2(including the NULLs) then add
OR id IS NULL to the WHERE clause.