The best SQL NOT NULL constraint Tutorial In 2024, In this tutorial you can learn SQL NOT NULL constraint,
In case of default, a table column accepts NULL values.
NOT NULL constraints forced the column does not accept NULL values.
NOT NULL constraint mandatory field always contains a value. This means that if you do not add value to a field, you can not insert a new record or update the record.
The following SQL mandatory "P_Id" column and the "LastName" column does not accept NULL values: