Page 144 - SQL

-- cannot insert
-- the value NULL into column 'MyCol1', table 'MyTable';
-- column does not allow nulls. INSERT fails.

Updating fields to NULL

Setting a field to NULL works exactly like with any other value:

UPDATE Employees
SET ManagerId = NULL
WHERE Id = 4

Inserting rows with NULL fields

For example inserting an employee with no phone number and no manager into the Employees
example table:

INSERT INTO Employees
(Id, FName, LName, PhoneNumber, ManagerId, DepartmentId, Salary, HireDate)
VALUES
(5, 'Jane', 'Doe', NULL, NULL, 2, 800, '2016-07-22') ;

Read NULL online: https://riptutorial.com/sql/topic/3421/null

https://riptutorial.com/ 126