自学教程：Python与数据库的交互问题小结

import pymongo client = pymongo.MongoClient()db = client["database_name"]  # 跟上数据库名collection = db["set_name"]  # 指定集合名

collection.insert_one({"name":"kongshang","age":12})

collection.find()

collection.update_one({"name":"kongshang"},{'$set':{"age":13}})

collection.delete_one({"name":"kongshang"})

import pymongo  class MyMonDB:    def __init__(self, database, collection):  # 数据库及集合        self.client = pymongo.MongoClient()  # 连接数据库使用        self.db = self.client[database]  # 指定使用的数据库        self.col = self.db[collection]  # 指定使用的集合     def insert(self, data, onlyOne=True):  # onlyOne用来控制插入单条还是多条数据        if onlyOne:            self.col.insert_one(data)        else:            self.col.insert_many(data)            def find(self, query=None, onlyOne=True):  # query是查询条件        if onlyOne:            ret = self.col.find_one(query)            return ret        else:            ret = self.col.find(query)            return list(ret)     def update(self, data_old, data_new, onlyOne=True):        if onlyOne:            self.col.update_one(data_old, {"$set": data_new})        else:            self.col.update_many(data_old, {"$set": data_new})     def delete(self, data, onlyOne=True):        if onlyOne:            self.col.delete_one(data)        else:            self.col.delete_many(data) 

import pymysql# 连接mysqldb_config = {    "host": "127.0.0.1",    "port": 3306,    "user": "admin",    "password": "qwe123",    "db": "stu",  # 指定操作的数据库    "charset": "utf8"} conn = pymysql.connect(**db_config)  # mysql登录 **是字典拆包print(conn)

cur = conn.cursor()  # 返回一个执行数据库命令游标对象，通过游标对象执行SQL命令cur.execute("INSERT INTO stu (id, name) VALUES (1, 'nihao'),(2, 'ci')")  # 执行SQL命令执行插入命令conn.commit()  # 事务，提交保存cur.close()  # 关闭游标对象conn.close()  # 关闭数据库

cur.execute("SELECT * FROM stu")  # 执行SQL命令# print(list(cur))# print(cur.fetchone())  # 查询单条# print(cur.fetchmany(3))  # 查询多条print(cur.fetchall())  # 查询所有

try:    cur.execute("INSERT INTO stu (id, name) VALUES (1, 'nihao'), (2, 'ci')")except Exception as e:    print(e)    conn.rollback()  # 事务回滚else:    conn.commit()  # 事务提交finally:    cur.close()  # 关闭游标对象    conn.close()  # 关闭数据库

import redis # 登录数据库# host ip地址# decode_responses get获得键值时 True返回字符串数据，默认是False二进制数据# db 指定数据库，默认为1red = redis.StrictRedis(host="127.0.0.1", decode_responses=True, db=2)

# 字符串red.set("num", 1)print(red.get("num"))print(red.type("num"))red.delete('num')# 综上，调用Redis数据库的方法是red.[输入redis数据库操作命令]()