SELECT JOB_TITLES.JOB_TITLE
FROM EMPLOYEES, INCUMBENTS, POSITIONS, JOB_TITLES
WHERE EMPLOYEES.FIRST_NAME="Bob"
              AND EMPLOYEES.SSN=INCUMBENTS.SSN
              AND INCUMBENTS.PCN=POSITIONS.PCN
              AND POSITIONS.JOB_TITLE_CODE1=JOB_TITLES.JOB_TITLE_CODE
              AND INCUMBENTS.START_DATE <= DATE()
              AND INCUMBENTS.END_DATE> DATE();
