1Z1-047 試験問題を無料オンラインアクセス

Which two statements are true regarding constraints? (Choose two.)

• A.A column with the UNIQUE constraint can contain NULL.
• B.A constraint is enforced only for the INSERT operation on a table.
• C.A foreign key cannot contain NULL values.
• D.A constraint can be disabled even if the constraint column contains data.
• E.All the constraints can be defined at the column level as well as the table level

Which statements are true regarding the hierarchical query in Oracle Database 10g? (Choose all that apply.

• A.You cannot specify conditions when you retrieve data by using a hierarchical query.
• B.It is possible to retrieve data in top-down or bottom-up hierarchy.
• C.It is possible to retrieve data only in top-down hierarchy.
• D.It is possible to remove an entire branch from the output of the hierarchical query.

Evaluate the following SQL statements that are issued in the given order:
CREATE TABLE emp
(emp_no NUMBER(2) CONSTRAINT emp_emp_no_pk PRIMARY KEY,
enameVARCHAR2(15),
salary NUMBER(8,2),
mgr_no NUMBER(2) CONSTRAINT emp_mgr_fk REFERENCES emp);
ALTER TABLE emp
DISABLE CONSTRAINT emp_emp_no_pk CASCADE;
ALTER TABLE emp
ENABLE CONSTRAINT emp_emp_no_pk;
What would be the status of the foreign key EMP_MGR_FK?

• A.It would remain disabled and can be enabled only by dropping the foreign key constraint and re-creating it.
• B.It would be automatically enabled and deferred.
• C.It would remain disabled and has to be enabled manually using the ALTER TABLE command.
• D.It would be automatically enabled and immediate.

Evaluate the following command:
CREATE TABLE employees (employee_id NUMBER(2) PRIMARY KEY, last_name VARCHAR2(25) NOT NULL, department_id NUMBER(2), job_id VARCHAR2(8), salary NUMBER(10,2)); You issue the following command to create a view that displays the IDs and last names of the sales staff in the organization: CREATE OR REPLACE VIEW sales_staff_vu AS SELECT employee_id, last_name job_id FROM employees WHERE job_id LIKE 'SA_%' WITH CHECK OPTION;
Which statements are true regarding the above view? (Choose all that apply.)

• A.It allows you to update the job ids of the existing sales staff to any other job id in the EMPLOYEES table.
• B.It allows you to delete the details of the existing sales staff from the EMPLOYEES table.
• C.It allows you to insert the IDs, last names and job ids of the sales staff from the view if it is used in multitable INSERT statements.
• D.It allows you to insert details of all new staff into the EMPLOYEES table.

View the Exhibit and examine the structure of the EMPLOYEES table.
You want to display all employees and their managers having 100 as the MANAGER_ID. You want the output in two columns: the first column would have the LAST_NAME of the managers and the second column would have LAST_NAME of the employees.
Which SQL statement would you execute?

• A.SELECT m.last_name "Manager", e.last_name "Employee"
  FROM employees m JOIN employees e
  WHERE m.employee_id = e.manager_id AND e.manager_id=100;
• B.SELECT m.last_name "Manager", e.last_name "Employee"
  FROM employees m JOIN employees e
  ON m.employee_id = e.manager_id
  WHERE e.manager_id=100;
• C.SELECT m.last_name "Manager", e.last_name "Employee"
  FROM employees m JOIN employees e
  ON e.employee_id = m.manager_id
  WHERE m.manager_id=100;
• D.SELECT m.last_name "Manager", e.last_name "Employee"
  FROM employees m JOIN employees e
  ON m.employee_id = e.manager_id
  WHERE m.manager_id=100;