Employees enrolled in a medical event(Executive Health Checkup) in Oracle HRMS

SELECT papf.employee_number employee_id, papf.full_name NAME,
       pe.TYPE || ' - ' || pe.date_start || '-' || pe.date_end event_name,
       org.NAME diagnostic_centre, pac.segment3 planning_to_visit        
--       pac.id_flex_num, pac.analysis_criteria_id  ,pe.event_id
FROM   per_analysis_criteria pac,
       hr.per_all_people_f papf,
       per_events pe,
       hr.hr_all_organization_units org
 WHERE papf.employee_number = :employee_number            
   AND TO_CHAR (papf.person_id) = pac.segment30
   AND pac.segment1 = TO_CHAR (pe.event_id)
   AND pe.TYPE = 'EHC'
   AND TO_CHAR (organization_id) IN (segment2)
   AND TRUNC (SYSDATE) BETWEEN TRUNC (papf.effective_start_date)
                           AND TRUNC (papf.effective_end_date)
   AND org.NAME IN (
          SELECT VALUE
            FROM pay_user_tables tbl,
                 pay_user_columns col,
                 pay_user_column_instances_f inst
           WHERE col.user_table_id = tbl.user_table_id
             AND inst.user_column_id = col.user_column_id
             AND user_table_name = 'GP Regional Units'
             AND col.user_column_name LIKE 'Regional EHC'
             AND inst.effective_end_date > SYSDATE);