单项选择题 Examine the structure of the EMP_DEPT_VU view: Column Name Type Remarks EMPLOYEE_ID NUMBER From the EMPLOYEES table EMP_NAME VARCHAR2(30) From the EMPLOYEES table JOB_ID VARCHAR2(20) From the EMPLOYEES table SALARY NUMBER From the EMPLOYEES table DEPARTMENT_ID NUMBER From the DEPARTMENTS table DEPT_NAME VARCHAR2(30) From the DEPARTMENTS table Which SQL statement produces an error?()
多项选择题 Examine the SQL statement that creates ORDERS table: CREATE TABLE orders (SER_NO NUMBER UNIQUE, ORDER_ID NUMBER, ORDER_DATE DATE NOT NULL, STATUS VARCHAR2(10) CHECK (status IN (CREDIT, CASH)), PROD_ID NUMBER REFERENCES PRODUCTS(PRODUCT_ID), ORD_TOTAL NUMBER, PRIMARY KEY (order_id, order_date)); For which columns would an index be automatically created when you execute the above SQL statement? ()
单项选择题 Evaluate this SQL statement: SELECT ename, sal, 12*sal+100 FROM emp; The SAL column stores the monthly salary of the employee. Which change must be made to the above syntax to calculate the annual compensation as "monthly salary plus a monthly bonus of $100, multiplied by 12"?()