单项选择题
A. SELECT last_name FROM EMP WHERE last_ name LIKE '_A%';
B. SELECT last_name FROM EMP WHERE last name ='*A%'
C. SELECT last_name FROM EMP WHERE last name ='_A%';
D. SELECT last_name FROM EMP WHERE last name LIKE '*A%'
多项选择题 The ORDERS table has these columns: The ORDERS table tracks the Order number, the order total, and the customer to whom the Order belongs. Which two statements retrieve orders with an inclusive total that ranges between 100.00 and 2000.00 dollars?（）
单项选择题 Examine the data from the ORDERS and CUSTOMERS tables. ORDERS ORD_ID ORD_DATE CUST_ID 12-JAN- 100 15 10000 09-MAR- 101 40 8000 09-MAR- 102 35 12500 15-MAR- 103 15 12000 25-JUN- 104 15 6000 18-JUL- 105 20 5000 106 18-JUL- 35 7000 21-JUL- 107 20 6500 04-AUG- 109 10 8000 CUSTOMERS CUST_ID CUST_NAME CITY 10 Smith Los Angeles 15 Bob San Francisco 20 Martin Chicago 25 Mary New York 30 Rina Chicago 35 Smith New York 40 Lind New York Evaluate the SQL statement: SELECT * FROM orders WHERE cust_id = (SELECT cust_id FROM customers WHERE cust_name = Smith); What is the result when the query is executed?（）
单项选择题 Examine the structure of the EMPLOYEES, DEPARTMENTS, and TAX tables. EMPLOYEES NOT NULL, Primary EMPLOYEE_ID NUMBER Key VARCHAR2 EMP_NAME (30) VARCHAR2 JOB_ID (20) SALARY NUMBER References MGR_ID NUMBER EMPLOYEE_ID column DEPARTMENT_ID NUMBER Foreign key to DEPARTMENT_ID column of the DEPARTMENTS table DEPARTMENTS NOT NULL, DEPARTMENT_ID NUMBER Primary Key VARCHAR2 DEPARTMENT_NAME |30| References MGR_ID column MGR_ID NUMBER of the EMPLOYEES table TAX MIN_SALARY NUMBER MAX_SALARY NUMBER TAX_PERCENT NUMBER For which situation would you use a nonequijoin query?（）