SELECT
  CaseGroups.caseID,
  CaseGroups.concernRoleID,
  CaseHeader.concernRoleID
INTO
  :caseID,
  :concernRoleID,
  :primaryClientID 
FROM
  CaseGroups,
  CaseHeader 
WHERE CaseGroups.groupCode = :groupCode 
  AND CaseHeader.caseID = CaseGroups.caseID 
  AND CaseGroups.startDate <= :startDate 
  AND 
  (
    CaseGroups.endDate >= :endDate 
    OR CaseGroups.endDate IS NULL 
  )