var obj=db.noCheckOnWork.find({"time":{$regex:/[^x00-xff][^/();@!$&*%#~]$/i}});
while(obj.hasNext())


{


  var doc=obj.next();


  var new_data="2017-11-20 18:41:57 Mon";


  db.noCheckOnWork.update({_id:doc._id},{$set:{"time":new_data}},false,true)
  }