mongo插入文档

score是已经创建的集合
db.score.insert({"_id": 103, "subject": "语文", "score": 55, "stuId": 1002}) 

db.score.save({"_id": 102, "subject": "数学", "score": 80, "stuId": 1002}) =>save操作的_id如果存在，则做更新

db.score.insertMany({"_id": 103, "subject": "语文", "score": 55, "stuId": 1002}，

                                 {"_id": 104, "subject": "语文", "score": 55, "stuId": 1003}) 

db.score.insertOne({"_id": 105, "subject": "语文", "score": 55, "stuId": 1004})