EMPLOYEES_ID 및 LOGIN_ID 열의 값이 null이 아닌 고유한 값이어야 하는 EMPLOYEES 테이블을 만들어야 합니다. (두 개를 선택하세요.) 필요한 테이블을 생성하는 두 가지 SQL 문은 무엇입니까?
A. CREATE TABLE employees(employee_id NUMBER,Login_id NUMBER,Employee_name VARCHAR2(100),Hire_date DATE,CONSTRAINT emp_id_ukUNIQUE (employee_id, login_id));
B. CREATE 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. CREATE TABLE employees(employee_id NUMBER CONSTRAINT emp_id_pk PRIMARY KEY, Login_id NUMBER UNIQUE, Employee_name VARCHAR2(25),Hire_date DATE);
D. CREATE 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. CREATE 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));