如何刪除 mongodb 和 pymogo 上的子文檔 (How to delete a subdocument on mongodb and pymogo)

問題描述

如何刪除 mongodb 和 pymogo 上的子文檔 (How to delete a subdocument on mongodb and pymogo)

大家好，我在使用 MongoDB 中的某些數組時遇到了一些問題。

我正在嘗試從收集代理中刪除帶有 {name:"projeto1"} 的子文檔。

有辦法訪問並刪除嗎？

from pprint import pprint
from pymongo import MongoClient
from pymongo import ReturnDocument
from bson.objectid import ObjectId
import json
import jsonpickle
from bson import json_util

class GetAgents:
    def __init__(self):
        self.client = MongoClient('localhost',27017)
        self.db = self.client['mindnet'] #nome do banco
        self.collection_agents = self.db['AGENTS'] #nome da coleção


    def create_backup(self):
        self.collection_backup = self.db['BACKUP'] #nome da coleção
        all_agents = self.collection_agents.find({})
        a = list(all_agents)
        self.collection_backup.insert_many(a)

    def remove_session(self, _agente, _projeto):




agent = GetAgents()
try:
    agent.create_backup()
    agent.remove_session('agente1','projeto2')
except:
    agent.remove_session('agente1', 'projeto2')

這就是數據庫現在的工作方式，我想按名稱刪除

參考解法

方法 1:

You need the pop command to remove a list element.

Try this example

import pymongo

db = pymongo.MongoClient()['mydatabase']
db.doc.insert_one({'name': 'a',
                   'sessions': [{'model': 0},
                                {'model': 1},
                                {'model': 2}]})

doc = db.doc.find_one({'name': 'a'}, {'_id': 0})
print(doc)
doc['sessions'].pop(1)
db.doc.replace_one({'name': 'a'}, doc, upsert=True)
doc = db.doc.find_one({'name': 'a'}, {'_id': 0})
print(doc)

gives:

{'name': 'a', 'sessions': [{'model': 0}, {'model': 1}, {'model': 2}]}
{'name': 'a', 'sessions': [{'model': 0}, {'model': 2}]}

(by Alysson Drews、Belly Buster)

參考文件

1. How to delete a subdocument on mongodb and pymogo (CC BY‑SA 2.5/3.0/4.0)