SELECT
  taskID,
  subject,
  priority,
  status,
  dueDateTime,
  reservedBy
INTO
  :taskID,
  :subject,
  :priority,
  :status,
  :dueDateTime,
  :reservedBy 
FROM
  Task_wa 
WHERE 
  (
    
    (
      taskID = :taskID 
    ) 
    OR 
    (
      :taskIDIsNull <> '0' 
    ) 
  ) 
  AND 
  (
    
    (
      priority = :priority 
    ) 
    OR 
    (
      :priority IS NULL 
    ) 
  ) 
  AND 
  (
    
    (
      status = :status 
    ) 
    OR 
    (
      :status IS NULL 
    ) 
  ) 
  AND 
  (
    
    (
      reservedBy = :reservedBy 
    ) 
    OR 
    (
      :reservedBy IS NULL 
    ) 
  ) 
ORDER BY Task_wa.taskID