Negating Conditions with the NOT Operator
Of all the conditions tested by the logical operators discussed here, there is a way to negate each one of these operators to change the condition's viewpoint.
The NOT operator reverses the meaning of the logical operator with which it is used. The NOT can be used with the following operators in the following methods:
IS NOT NULL
Each method is discussed in the following sections. First, let's look at how to test for inequality.
You have learned how to test for inequality using the <> operator. Inequality is worth mentioning in this section because to test for it, you are actually negating the equality operator. The following is a second ...