1. new Timestamp()

2. Date(0)

3.ISOData()

job2 = {"id" : 2,"status" : 1,"created" : new Timestamp(), "stated" : Date(0),"ended" : ISODate(),{        "id" : 2,        "status" : 1,        "created" : Timestamp(0, 0),        "stated" : "Thu Oct 25 2012 10:33:08 GMT+0800 (CST)",        "ended" : ISODate("2012-10-25T02:33:08.201Z"),        "target_type" : 1,        "action" : 2}

 C++

1. BSONObj o = BSON("date" << std::time(0));

BSONObj p = BSON( "created" << DATENOW );

References: