单项选择题
A.SELECT employee_id, last_name, job_id FROM employees WHERE job_id LIKE '%SA\_%' ESCAPE '\';
B.SELECT employee_id, last_name, job_id FROM employees WHERE job_id LIKE '%SA_';
C.SELECT employee_id, last_name, job_id FROM employees WHERE job_id LIKE '%SA_' ESCAPE "\";
D.SELECT employee_id, last_name, job_id FROM employees WHERE job_id = '%SA_';
单项选择题 Evaluate this SQL statement: SELECT e.EMPLOYEE_ID,e.LAST_NAME,e.DEPARTMENT_ID, d.DEPARTMENT_NAME FROM EMPLOYEES e, DEPARTMENTS d WHERE e.DEPARTMENT_ID = d.DEPARTMENT_ID; In the statement, which capabilities of a SELECT statement are performed?（）
单项选择题 Evaluate these two SQL statements: SELECT last_name, salary , hire_date FROM EMPLOYEES ORDER BY salary DESC; SELECT last_name, salary , hire_date FROM EMPLOYEES ORDER BY 2 DESC; What is true about them?（）
多项选择题 What are two reasons to create synonyms? （）