function diff(datasetClientJson, localRecords, next) {
      var recordsDiff = diffRecords(syncUtil.convertToObject(localRecords), syncUtil.convertToObject(records));
      return next(null, datasetClientJson, recordsDiff);
    }
function diff(datasetClientJson, localRecords, next) {
      var recordsDiff = diffRecords(syncUtil.convertToObject(localRecords), syncUtil.convertToObject(records));
      return next(null, datasetClientJson, recordsDiff);
    }
function diff ( datasetClientJson , localRecords , next ) { var recordsDiff = diffRecords ( syncUtil . convertToObject ( localRecords ) , syncUtil . convertToObject ( records ) ) ; return next ( null , datasetClientJson , recordsDiff ) ; }
to reduce the number of db operations, we try to compute only the records that need to be changed here.
to reduce the number of db operations we try to compute only the records that need to be changed here .