Adam works as a Database Administrator for Domain.com. He creates a table named Students.
The structure of the Students table is as follows:
CREATE TABLE Students (
Stud_ID NUMBER(3) NOT NULL,
Stud_Name VARCHAR2(25) NOT NULL,
Stud_Phone VARCHAR2(9) NOT NULL,
Stud_Address VARCHAR2(50));
Adam wants to restrict the values in the Stud_Phone column to numeric. Which of the following
statements are true if Adam wants to modify the structure of the Students table so that the data
type of the Stud_Phone column changes from VARCHAR2 to NUMBER?
Each correct answer represents a complete solution. Choose two.
A.
Adam cannot modify the data type of the column if there is data in the column.
B.
Adam can modify the data type of the column by using the UPDATE command.
C.
Adam cannot modify the data type of the column but can increase the length of the column
even if there is data in the column.
D.
Adam can modify the data type of the column by using the CHANGE command.