Chapter 3, Problem 6RQ

Explanation of Solution

 Null value:

 A NULL value is a special value that is used to represent the missing value...

Explanation of Solution

 Identifying columns that cannot accept null values:

 The columns that cannot accept null values can be identified using “NOT NULL” clause in a “CREATE TABLE” command.

Creating table “EMPLOYEE”:

CREATE TABLE EMPLOYEE (

EMP_NUM     CHAR(3) PRIMARY KEY,

EMP_LNAME      VARCHAR(15) NOT NULL,

EMP_F...