mongodb - save()和insert()的区别

遇到_id相同的情况下：
insert操作会报错；save完成保存操作

> db.person.find()
> db.person.insert({"_id":1,age:1,name:"hh"})
WriteResult({ "nInserted" : 1 })
> db.person.find()
{ "_id" : 1, "age" : 1, "name" : "hh" }

#insert一个"_id"已经存在的文档
> db.person.insert({"_id":1,age:10,name:"hh02"})
WriteResult({
        "nInserted" : 0,
        "writeError" : {
                "code" : 11000,
                "errmsg" : "E11000 duplicate key error collection: foobar.person index: _id_ dup key: { : 1.0 }"
        }
})
> db.person.find()
{ "_id" : 1, "age" : 1, "name" : "hh" }

#save一个"_id"已经存在的文档
> db.person.save({"_id":1,age:10,name:"hh02"})
WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })
> db.person.find()
{ "_id" : 1, "age" : 10, "name" : "hh02" }
>