Structure of the ORDERITEMS table

-If a PRIMARY KEY constraint,named ORDERITEMS_PK,exists for the ORDER# and ITEM# columns of the ORDERITEMS table,which of the following commands will drop the constraint?
A) ALTER TABLE orderitems DROP PRIMARY KEY CONSTRAINT;
B) ALTER TABLE orderitems DELETE CONSTRAINT orderitems_pk;
C) ALTER TABLE orderitems DROP PRIMARY KEY;
D) ALTER TABLE orderitems MODIFY PRIMARY KEY CONSTRAINT DROP;

Question

​Structure of the ORDERITEMS table
 
-If a PRIMARY KEY constraint,named ORDERITEMS_PK,exists for the ORDER# and ITEM# columns of the ORDERITEMS table,which of the following commands will drop the constraint?​
A) ALTER TABLE orderitems DROP PRIMARY KEY CONSTRAINT; 
B) ALTER TABLE orderitems DELETE CONSTRAINT orderitems_pk; 
C) ALTER TABLE orderitems DROP PRIMARY KEY; 
D) ​ALTER TABLE orderitems MODIFY PRIMARY KEY CONSTRAINT DROP;

Quizplus · Accepted Answer

The correct syntax for dropping a primary key constraint is to use the DROP PRIMARY KEY command followed by the name of the table. Therefore, option C is the correct answer. Option A is incorrect because it does not include the name of the constraint. Option B is incorrect because it uses the incorrect syntax for deleting a constraint. Option D is incorrect because it uses an incorrect syntax for modifying the primary key constraint.

​Structure of the ORDERITEMS Table

Structure of the ORDERITEMS Table