{ "_id" : ObjectId("585295e3b049609a5fb691c5"), "name" : "yyb", "age" : 21 } { "_id" : ObjectId("585295e3b049609a5fb691c6"), "name" : "yyb", "age" : 30 } { "_id" : ObjectId("585295e3b049609a5fb691c7"), "name" : "yyb", "age" : 40 } > db.user.update({...