• mongoDB-示例代码


    """
    pymongo模块操作示例
    用于数据增删改查索引聚合方法的参考
    """
    
    from pymongo import MongoClient
    
    #  创建数据库连接
    conn = MongoClient('localhost', 27017)
    
    #  创建数据库对象和集合对象
    db = conn.stu
    myset = db.class4
    
    #  数据操作
    
    # *********** insert **************
    # myset.insert_one({'name':'张铁林','King':'乾隆'})
    
    # myset.insert_many([{'name':'陈道明','King':'康熙'},
    #                    {'name':'张国立','King':'康熙'}])
    
    # myset.insert({"name":'唐国强',"King":'雍正'})
    
    # myset.insert([{"name":'陈建斌',"King":'雍正'},
    #               {"name":'聂远','King':"乾隆"}])
    
    # myset.save({'_id':1,'name':'吴奇隆',"King":'四爷'})
    # myset.save({'_id':1,'name':'郑少秋',"King":'乾隆'})
    
    # ************* find **************
    
    #  所有的操作符加引号,作为字符串表达
    cursor = myset.find({'name': {'$gt': '唐国强'}}, {'_id': 0})
    
    #  循环遍历得到的每一个结果都是文档字典
    # for i in cursor:
    #     print(i['name'],'---',i['King'])
    
    # print(cursor.next())  # 获取游标的下一个结果
    
    #  cursor调用limit,skip,sort后得到的仍然是结果游标对象
    # for i in cursor.skip(1).limit(3):
    #     print(i)
    
    # 按照king排序
    # for i in cursor.sort([('King',1)]):
    #     print(i)
    
    # r = myset.find_one({'King':'康熙'},{"_id":0})
    # print(r)
    
    # ************** update *************
    # myset.update_one({"King":'康熙'},
    #                  {'$set':{"king_name":'玄烨'}})
    
    # myset.update_many({"King":'雍正'},
    #                   {"$set":{'king_name':'胤禛'}})
    
    # myset.update({"King":'乾隆'},
    #                   {"$set":{'king_name':'弘历'}},
    #              multi=True)
    #
    # myset.update_one({"King":'光绪'},
    #                  {'$set':{"name":'邓超'}},
    #                  upsert=True)
    
    # ************ delete *************
    # myset.delete_one({'King':'乾隆'})
    # myset.delete_many({"king_name": None})
    # myset.remove({"King":'雍正'},multi=False)
    
    # r = myset.find_one_and_delete({'King':'乾隆'})
    # print(r)
    
    # *************** index ***************
    #  参数 'name' ==> [('name',1)]
    # index1 = myset.create_index('name')
    # index2 = myset.create_index([('name', -1)], 
    #                             name="NAME",sparse=True)
    #
    # print("index1 = ", index1)
    # print("index2 = ", index2)
    
    #  删除索引
    # myset.drop_index('NAME')
    # myset.drop_index([('name',1)])
    # myset.drop_indexes()
    
    #  查看索引
    # for i in myset.list_indexes():
    #     print(i)
    
    # ************ aggregation **********
    myset = db.class0  # 更换操作集合
    
    pipe = [
        {'$match': {'gender': {'$exists': True}}},
        {'$sort': {'age': 1}},
        {'$project': {'_id': 0}}
    ]
    
    cursor = myset.aggregate(pipe)
    
    for i in cursor:
        print(i)
    
    # 关闭连接
    conn.close()
    

      

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  • 原文地址:https://www.cnblogs.com/gyl10/p/11461139.html
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