需求

插入数据
在默认排序中 数据显示在中间而不是最后

实验思路：

• 按正常顺序插入x条数据
• 拿第一条数据 加字段 id不变 删除后加入

代码：

#!/usr/bin/python3
# encoding: utf-8 
# @Time    : 2019/1/3 11:37
# @Author  : zza
# @Email   : 740713651@qq.com
import datetime
import time
from pprint import pprint

import pymongo
from mongomock import ObjectId
from tqdm import tqdm

mongo_url = "mongodb://127.0.0.1:27017", 'sort_db'
mongo_db = pymongo.MongoClient(mongo_url[0])[mongo_url[1]]


def made_data():
    mongo_db['demo'].drop()
    print("开始造数据")
    for i in tqdm(range(10)):
        time.sleep(1)
        mongo_db['demo'].insert({"timestamp": datetime.datetime.now()})


def set_data():
    # 之前想造个数据放进去  保存一下 如何生成 _id
    # http://api.mongodb.com/python/current/api/bson/objectid.html
    pprint(list(mongo_db['demo'].find()))
    gen_time = datetime.datetime(2019, 1, 1, 14, 12, 26)
    dummy_id = ObjectId.from_datetime(gen_time)
    dummy_id = str(dummy_id)[:8] + "5c2da85ffc904a3c84335788"[8:]
    dummy_id = ObjectId(dummy_id)
    print(dummy_id)
    result = mongo_db['demo'].insert({"_id": dummy_id, "info": "id made by python", "timestamp": gen_time})
    print(result)
    pprint(list(mongo_db['demo'].find()))
    pprint(list(mongo_db['demo'].find({}).sort([("_id", -1)])))


def re_insert_first():
    a = mongo_db['demo'].find()[0]
    mongo_db['demo'].delete_one({"_id": a["_id"]})
    a.update({"info": "change by py"})
    mongo_db['demo'].insert(a)
    pprint(list(mongo_db['demo'].find()))


made_data()
# set_data()
re_insert_first()

发现还是不行

后期的解决方案 ：

在数据量不大的情况下
删除后面的数据
然后顺序插入