【单项选择题】
Examine the structure of the EMPLOYEES and DEPARTMENTS tables: EMPLOYEESColumn name Data type Remarks<br /> EMPLOYEE_ID NUMBER NOT NULL, Primary Key<br /> EMP_NAME VARCHAR2 (30)<br /> JOB_ID VARCHAR2 (20)<br /> SALARY NUMBER<br /> MGR_ID NUMBER References EMPLOYEE_ID COLUMN<br /> DEPARTMENT ID NUMBER Foreign key to DEPARTMENT ID column of the DEPARTMENTS table<br /> DEPARTMENTSColumn name Data type Remarks<br /> DEPARTMENT_ID NUMBER NOT NULL, Primary Key DEPARTMENT_NAME VARCHAR2(30)<br /> MGR_ID NUMBER References MGR_ID column of the EMPLOYEES table<br /> Evaluate this SQL statement:<br /> SELECT employee_id, e.department_id, department_name, salary<br /> FROM employees e, departments d<br /> WHERE e. department_id = d.department_id;<br /> Which SQL statement is equivalent to the above SQL statement? （）<p> Examine the structure of the EMPLOYEES and DEPARTMENTS tables: EMPLOYEESColumn name Data type Remarks<br /> EMPLOYEE_ID NUMBER NOT NULL, Primary Key<br /> EMP_NAME VARCHAR2 (30)<br /
A、A. SELECT employee_id, department_id, department_name, salary FROM employees WHERE department_id IN (SELECT department_id FROM departments);
B、B. SELECT employee_id, department_id, department_name, salary FROM employees NATURAL JOIN departments;
C、C. SELECT employee_id, d.department_id, department_name, salary FROM employees e JOIN departments d ON e.department _ id = d. department_id;
D、D. SELECT employee_id, department_id, department_name, Salary FROM employees JOIN departments USING (e.department_id, d.department_id);
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