测开之路五十一：代码实现MongoDB增删改查

Posted 2021-12-20 zhongyehai

 

初始化时连接、析构时断开连接

from pymongo import MongoClient


class Mogo(object):

    def __init__(self, host=‘127.0.0.1‘, port=27017):
        """ 初始化时连接 """
        self.connect = MongoClient(host, port)

    def __del__(self):
        """ 析构时断开连接 """
        self.connect.close()

插入：

def insert(self, database, collection, documents):
    """ 增：database: 数据库名、collection: 表名、documents: 数据 """
    _database = self.connect.get_database(database)  # 获取数据库对象
    _collection = _database.get_collection(collection)  # 获取表对象
    return _collection.insert_one(documents)

 

准备好几条数据

 

查找

如：查name为“XXX”的数据

def search(self, database, collection, filter):
    """ 查：database: 数据库名、collection: 表名、filter: 查找条件 """
    _database = self.connect.get_database(database)  # 获取数据库对象
    _collection = _database.get_collection(collection)  # 获取表对象
    return _collection.find(filter)

默认查出来是结果集

 

结果集可以转list，也可以用for循环取，取出来一个是list，一个是字典

 

增加过滤条件：使用projection

如：查sex=“男”的数据，且不返回id和sex

def search(self, database, collection, filter):
    """ 查：database: 数据库名、collection: 表名、filter: 查找条件 """
    projection = None
    if "projection" in filter:
        projection = filter.pop("projection")
    _database = self.connect.get_database(database)  # 获取数据库对象
    _collection = _database.get_collection(collection)  # 获取表对象
    return _collection.find(filter, projection)

 

删除：

def delet(self, database, collection, filter):
    """ 删：database: 数据库名、collection: 表名、filter: 查找条件 """
    _database = self.connect.get_database(database)  # 获取数据库对象
    _collection = _database.get_collection(collection)  # 获取表对象
    _collection.delete_one(filter)

如：删除之前插入的数据

 

再刷新，表里面已经没有数据了

 

更新：

def update(self, database, collection, filter, documents):
    """ 改：database: 数据库名、collection: 表名、filter: 查找条件、documents: 数据 """
    _database = self.connect.get_database(database)  # 获取数据库对象
    _collection = _database.get_collection(collection)  # 获取表对象
    _collection.update_one(filter, ‘$set‘: documents)

 

 

最后增查改删的代码

from pymongo import MongoClient


class Mogo(object):

    def __init__(self, host=‘127.0.0.1‘, port=27017):
        """ 初始化时连接 """
        self.connect = MongoClient(host, port)

    def __del__(self):
        """ 析构时断开连接 """
        self.connect.close()

    def insert(self, database, collection, documents):
        """ 增：database: 数据库名、collection: 表名、documents: 数据 """
        _database = self.connect.get_database(database)  # 获取数据库对象
        _collection = _database.get_collection(collection)  # 获取表对象
        return _collection.insert_one(documents)

    def search(self, database, collection, filter):
        """ 查：database: 数据库名、collection: 表名、filter: 查找条件 """
        projection = None
        if "projection" in filter:
            projection = filter.pop("projection")
        _database = self.connect.get_database(database)  # 获取数据库对象
        _collection = _database.get_collection(collection)  # 获取表对象
        return _collection.find(filter, projection)

    def update(self, database, collection, filter, documents):
        """ 改：database: 数据库名、collection: 表名、filter: 查找条件、documents: 数据 """
        _database = self.connect.get_database(database)  # 获取数据库对象
        _collection = _database.get_collection(collection)  # 获取表对象
        _collection.update_one(filter, ‘$set‘: documents)

    def delet(self, database, collection, filter):
        """ 删：database: 数据库名、collection: 表名、filter: 查找条件 """
        _database = self.connect.get_database(database)  # 获取数据库对象
        _collection = _database.get_collection(collection)  # 获取表对象
        _collection.delete_one(filter)