mongodb学习5--mongo的type类型

db.active.group({key:{id:1},cond:{cd:20160913,cid:"fgsdljsdv",aid:"54465"},reduce:function(obj,prev){prev.cnum++},initial:{cnum:0}}).forEach(
    function(x){
    var res1=db.active.find({cd:20160910,cid:'fgsdljsdv',aid:'54465',idfa:x.id});
    if(res1.hasNext()){
        x.cd=20160910,
        db.temp_1142922596_today.insert(x);
    }
  }
)

db.active.find({idfa:{$type:2}}).count()

Type Description	Type value
Double	1
String	2
Object	3
Array	4
Binary data	5
Object id	7
Boolean	8
Date	9
Null	10
Regular expression	11
JavaScript code	13
Symbol	14
JavaScript code with scope	15
32-bit integer	16
Timestamp	17
64-bit integer	18
Min key	255
Max key	127