您必須創建一個表 EMPLOYEES,其中列 EMPLOYEES_ID 和 LOGIN_ID 的值必須是唯一的且不能爲空。(選擇兩項。)哪兩條 SQL 語句可以創建所需的表?
A. REATE TABLE employees(employee_id NUMBER,Login_id NUMBER,Employee_name VARCHAR2(100),Hire_date DATE,CONSTRAINT emp_id_ukUNIQUE (employee_id, login_id));
B. REATE TABLE employees(employee_id NUMBER,login_id NUMBER,employee_name VARCHAR2(25),hire_date DATE,CONSTRAINT emp_id_pk PRIMARY KEY(employee_id,login_id));
C. REATE TABLE employees(employee_id NUMBER CONSTRAINT emp_id_pk PRIMARY KEY, Login_id NUMBER UNIQUE, Employee_name VARCHAR2(25),Hire_date DATE);
D. REATE TABLE employees(employee_id NUMBER,Login_id NUMBER,Employee_name VARCHAR2(100),Hire_date DATE,CONSTRAINT emp_id_uk UNIQUE(employee_id,login_id);CONSTRAINT emp_id_nn NOT NULL(employee_id,login_id));
E. REATE TABLE employees(employee_id NUMBER CONSTRAINT emp_id_nn NOT NULL, Login_id NUMBER CONSTRAINT login_id_nn NOT NULL,Employee_name VARCHAR2(100),Hire_date DATE,CONSTRAINT emp_id_ukUNIQUE (employee_id, login_id));