Choose two. Examine these statements: CREATE TABLE dept ( Deptno NUMBER PRIMARY KEY, dname VARCHAR2 (10) , Mgr NUMBER, CONSTRAINT dept_fkey FOREIGN KEY (mgr) REFERENCES emp (empno)) ; CREATE TABLE emp( Empno NUMBER PRIMARY KEY, ename VARCHAR2 (10) , Deptno NUMBER, CONSTRAINT emp_fkey FOREIGN KEY (deptno) REFERENCES dept (deptno) DISABLE) ; ALTER TABLE emp MODIFY CONSTRAINT emp_fkey ENABLE ; Which two are true? | 1Z0-082（322题）更20241031

多选题 Choose two. Examine these statements: CREATE TABLE dept ( Deptno NUMBER PRIMARY KEY, dname VARCHAR2 (10) , Mgr NUMBER, CONSTRAINT dept_fkey FOREIGN KEY (mgr) REFERENCES emp (empno)) ; CREATE TABLE emp( Empno NUMBER PRIMARY KEY, ename VARCHAR2 (10) , Deptno NUMBER, CONSTRAINT emp_fkey FOREIGN KEY (deptno) REFERENCES dept (deptno) DISABLE) ; ALTER TABLE emp MODIFY CONSTRAINT emp_fkey ENABLE ; Which two are true?

A、 The MGR column in the DEPT table will not be able to contain NULL values.

B、 Both foreign key constraint definitions must be removed from the CREATE TABLE statements, and be added with ALTER TABLE statements once both tables are created, for the two CREATE TABLE statements to execute successfully in the order shown.

C、 The CREATE TABLE EMP statement must precede the CREATE TABLE DEPT statement for all three statements to execute successfully.

D、 The DEPTNO column in the EMP table will be able to contain NULL values.

E、 All three statements execute successfully in the order shown.

F、 The DEPT_FKEY constraint definition must be removed from the CREATE TABLE DEPT statement, and be added with an ALTER TABLE statement once both tables are Created, for the two CREATE TABLE statements to execute successfully in the order shown.

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