1、哪一种 SQL 有错误
SELECT * FROM emp_dept_vu;B
SELECT department_id, SUM(salary) FROM emp_dept_vuGROUP BY department_id;C
SELECT department_id, job_id, AVG(salary)FROM emp_dept_vuGROUP BY department_id, job_id;D
SELECT job_id, SUM(salary)FROM emp_dept_vuWHERE department_id IN (10,20)GROUP BY job_idHAVING SUM(salary) > 0;E
没有一种错误,都是对的
2、两张表构造如下:EMPLOYEES(EMPLOYEE_ID NUMBER Primary KeyFIRST_NAME VARCHAR2(25)LAST_NAME VARCHAR2(25)HIRE_DATE DATE)NEW_EMPLOYEES(EMPLOYEE_ID NUMBER Primary KeyNAME VARCHAR2(60))哪一种删除语句是对的的
DELETE FROM employeesWHERE employee_id = (SELECT employee_idFROM employees);B
DELETE * FROM employeesWHERE employee_id = (SELECT employee_idFROM new_employees);C
DELETE FROM employeesWHERE employee_id IN (SELECT employee_idFROM new_employeesWHERE name ='Carrey');