出自:Oracle认证
Examine the structure of the EMPLOYEES table: EMPLOYEE_ID NUMBER Primary Key FIRST_NAME VARCHAR2(25) LAST_NAME VARCHAR2(25) Which three statements inserts a row into the table? （）
A:INSERT INTO employees VALUES (NULL, 'JOHN','Smith');
B:INSERT INTO employees( first_name, last_name) VALUES ('JOHN','Smith');
C:INSERT INTO employees VALUES ('1000','JOHN','NULL');
D:INSERT INTO employees(first_name,last_name, employee_id) VALUES ('1000, 'john','Smith');
E:INSERT INTO employees (employee_id) VALUES (1000);
F:INSERT INTO employees (employee_id, first_name, last_name) VALUES ( 1000, 'john',");
Evaluate this SQL statement: SELECT e.EMPLOYEE_ID,e.LAST_NAME,e.DEPARTMENT_ID, d.DEPARTMENT_NAME FROM EMP e, DEPARTMENT d WHERE e.DEPARTMENT_ID = d.DEPARTMENT_ID; In the statement, which capabilities of a SELECT statement are performed?（）
A:Selection, projection, join
B:Difference, projection, join
C:Selection, intersection, join
D:Intersection, projection, join
E:Difference, projection, product
When the doSomething method is called， after which line does the Object created in line 5 become available for garbage collection？（）
What can directly access and change the value of the variable name?（）