What will happen if you try to use the INSERT command to insert a NULL value into a column that has been assigned a PRIMARY KEY constraint?
A) The command will execute because a PRIMARY KEY value can be NULL.
B) An error message is returned and the row is not added to the table.
C) The command will execute because only a UNIQUE constraint forbids NULL values.
D) An error message is returned but the unaffected portion of the row is added to the table.

Question

What will happen if you try to use the INSERT command to insert a NULL value into a column that has been assigned a PRIMARY KEY constraint? ​
A) ​The command will execute because a PRIMARY KEY value can be NULL.
B) ​An error message is returned and the row is not added to the table.
C) ​The command will execute because only a UNIQUE constraint forbids NULL values.
D) ​An error message is returned but the unaffected portion of the row is added to the table.

Quizplus · Accepted Answer

A PRIMARY KEY constraint by definition prohibits NULL values in the column(s) it is assigned to. Attempting to insert a NULL value would violate this constraint and result in an error message.

What Will Happen If You Try to Use the INSERT