Negation
The NOT operator reverses, or negates, the meaning of a qualification.
In the following example, the access method returns only
rows with an lname value other than SMITH:
WHERE NOT lname = "SMITH"The
NOT operator can also reverse the result of a Boolean expression.
In the next example, the access method rejects rows that have southwest or northwest in
the region column:
WHERE NOT (region = "southwest" OR region = “northwest”)