dbms.sql

/* QUESTION 1*/

SELECT FIRST_NAME,MANAGER_ID,HIRE_DATE

FROM employees

WHERE MANAGER_ID IN(30,40,50) IS FALSE
AND FIRST_NAME LIKE "%a%r%" OR "%r%a%"
AND HIRE_DATE BETWEEN '1987-3-1' AND HIRE_DATE<='1987-10-31';


/* QUESTION 2 */


SELECT * FROM job_history

ORDER BY START_DATE  DESC,EMPLOYEE_ID ASC;



/* QUESTION 3 */

SELECT MAX_SALARY, MIN_SALARY FROM jobs ORDER BY (MAX_SALARY-MIN_SALARY) DESC LIMIT 1,1;


/* QUESTION 4 */


SELECT  EMPLOYEE_ID, FIRST_NAME, HIRE_DATE,

       CASE 
       WHEN HIRE_DATE> "1987-9-1" THEN "Junior"
       WHEN HIRE_DATE> "1987-5-1" THEN "Mid-level Senior"
       ELSE "Senior" END
       
AS "Experience Level"
       
FROM employees;