Megatest

	      (coldat (hash-table-ref/default data first #f)))
	 (if (not coldat)(let ((newht (make-hash-table)))
			   (hash-table-set! data first newht)
			   (set! coldat newht)))
	 (hash-table-set! coldat rest run)))
     runs)
    data))

;; given ordered data hash return a-keys
;;
(define (pgdb:ordered-data->a-keys ordered-data)
  (sort (hash-table-keys ordered-data) string>=?))

;; given ordered data hash return b-keys
;;
(define (pgdb:ordered-data->b-keys ordered-data a-keys)
  (delete-duplicates
   (sort (apply
	  append
	  (map (lambda (sub-key)
		 (let ((subdat (hash-table-ref ordered-data sub-key)))
		   (hash-table-keys subdat)))
	       a-keys))
	 string>=?)))

;; given ordered data hash return a-keys
;;
(define (pgdb:ordered-data->a-keys ordered-data)
  (sort (hash-table-keys ordered-data) string>=?))

;; given ordered data hash return b-keys