anchor.diff:                                   (if (consp c)
                                        (create-col (car c)
                                                    (get-pos :db ',db :table tbl)
  -                                                 :pred (eval (cdr c)))
  +                                                 :pred (eval (cadr c)))
                                        (create-col c
                                                    (get-pos :db ',db :table tbl))))
                                cols))
  
positive.code:          (error "Invalid argument, [integer] or selector only")
           (with-lock
             (loop :for i :in p
                :collect (loop :for j :from 0 :to (1- (length table))
                            :collect (nth i
                                          (getf (aref table j) :data)))))))
      (selector
       (let ((pivot (lookup-table (selector-col p) table)))
         (if (equal pivot 'DNE)
             (error "Invalid selector with pivot column: ~A" (selector-col p))
             (with-lock
               (loop :for i :from 0 :to (1- (length pivot))
                  :when (funcall (selector-pred p) (nth i pivot))
                  :collect (loop :for j :from 0 :to (1- (length table))
                              :collect (nth i (getf (aref table j) :data))))))))))
  
  ;;N could be a function that takes the index and the current value
  (defun update (p n table)
  
negative.code:            (with-lock
               (let* ((l (1- (length pivot)))
                      (r
                        (loop :for i :from 0 :to l
                              :when (not (funcall (selector-pred p) (nth i pivot)))
                                :collect (loop :for j :from 0 :to (1- (length table))
                                               :collect (nth i (getf (aref table j) :data)))))
                      (res (loop :for i :from 0 :to (1- (length (car r)))
                                 :collect (mapcar #'(lambda (l) (nth i l)) r))))
                 (loop :for i :from 0 :to (1- (length table))
                       :do (setf (getf (aref table i) :data)
                                 (nth i res))))))))))
  
  (defun lookup (p table)
    (typecase p
  