Migration-only method

        Notes:
            Precondition: buid cache must be disabled

async def editNodeNdef(self, oldv, newv):
        '''
        Migration-only method

        Notes:
            Precondition: buid cache must be disabled
        '''
        assert self.buidcache.disabled

        oldb = s_common.buid(oldv)
        newb = s_common.buid(newv)

        pvoldval = s_msgpack.en((oldb,))
        pvnewval = s_msgpack.en((newb,))

        oldfenc = oldv[0].encode() + b'\x00'
        newfenc = newv[0].encode() + b'\x00'

        newprel = b'*' + newv[0].encode()

        newnindx = self.core.model.prop(newv[0]).type.indx(newv[1])

        # avoid any potential iter/edit issues...
        todo = list(self.layrslab.scanByPref(oldb, db=self.bybuid))

        for lkey, lval in todo:

            proputf8 = lkey[32:]
            valu, indx = s_msgpack.un(lval)

            # for the *<form> prop, the byprop index has <form><00><00><indx>
            if proputf8[0] == 42:

                newpropkey = newfenc + b'\x00' + newnindx

                if indx is not None:
                    oldpropkey = oldfenc + b'\x00' + indx
                    if not self.layrslab.delete(oldpropkey, pvoldval, db=self.byprop): # pragma: no cover
                        logger.warning(f'editNodeNdef del byprop missing for {repr(oldv)} {repr(oldpropkey)}')

                self.layrslab.put(newpropkey, pvnewval, dupdata=True, db=self.byprop)

                byts = s_msgpack.en((newv[1], newnindx))
                self.layrslab.put(newb + newprel, byts, db=self.bybuid)

            else:

                # <prop><00><indx>
                propindx = proputf8 + b'\x00' + indx

                if proputf8[0] in (46, 35): # ".univ" or "#tag"
                    self.layrslab.put(propindx, pvnewval, dupdata=True, db=self.byuniv)
                    self.layrslab.delete(propindx, pvoldval, db=self.byuniv)

                oldpropkey = oldfenc + propindx
                newpropkey = newfenc + propindx

                if not self.layrslab.delete(oldpropkey, pvoldval, db=self.byprop): # pragma: no cover
                    logger.warning(f'editNodeNdef del byprop missing for {repr(oldv)} {repr(oldpropkey)}')

                self.layrslab.put(newpropkey, pvnewval, dupdata=True, db=self.byprop)
                self.layrslab.put(newb + proputf8, lval, db=self.bybuid)

            self.layrslab.delete(lkey, db=self.bybuid)