Which of the following commands would cause the end of a transaction? (Select three.)

You have noticed a change of performance in your production Oracle 12c database. In order to know what was the change which has caused this performance difference, which method or feature would you use?

The STUDENTS table needs to be modified in order to add a primary key on the STUDENT_ID column. 

At the moment, the table is empty. 

Which of the following statements would accomplish this task?

From the SALES table, you need to display the details of those products which contain the string '_D123' in the PROD_ID column. In order to get the required output, which WHERE clause could be used in the SELECT statement?

Which of the following statements would add a constraint to ensure that the CUSTOMER_NAME column of the CUSTOMERS table holds a value?

Examine the structure of the PROMOTIONS table in the Exhibit that follows. 

Based on the PROMOTIONS table, you must display the names of all promos done after January 1, 2001, starting with the last promotion. 

Which queries would produce the required outcome? (Select all options that may apply.)

Analyze the data in the EMPLOYEES and DEPARTMENTS tables: EMPLOYEES DEPARTMENTS 

- On the EMPLOYEES table, the primary key is EMPLOYEE_ID. MGR_ID is the ID manager which refers to the EMPLOYEE_ID; the primary key on the DEPARTMENTS table is DEPARTMENT_ID. 

Examine the following UPDATE statement: 

UPDATE employees - SET mgr_id = (SELECT mgr_id FROM employees WHERE dept_id = (SELECT department_id FROM departments WHERE department_name = 'Administration')), Salary = (SELECT salary FROM employees WHERE emp_name = 'Smith') WHERE job_id = 'IT_ADMIN'; 

What would be the outcome of executing the above statement?

Which of the following statements are true regarding multiple-row subqueries? (Select three.)