Python pymysql操作MySQL详细

import pymysql

# 创建连接
con = pymysql.connect(
                        host='localhost',
                        port=3306,
                        user='root',
                        password='123456',
                        database='test',
                        charset='utf8'
)
# 创建游标
cursor = con.cursor()

# 执行新增SQL，返回受影响行数
row1 = cursor.execute("insert into user (username, password) values ('username3','password3')")
print(row1)

# 执行更新SQL，返回受影响行数
row2 = cursor.execute("update user set password = '123456' where id > 2;")
# 执行查询SQL
res = cursor.execute("SELECT * FROM user;")
result = cursor.fetchall()
for info in result:
    print(info[0], info[1])
# 提交，不然无法保存新增或者更新的数据
con.commit()
# 关闭游标
cursor.close()
# 关闭连接
con.close()

import pymysql


class MysqlHelper:
    def __init__(self, config):
        self.host = config["host"]
        self.port = config["port"]
        self.user = config["user"]
        self.password = config["password"]
        self.db = config["db"]
        self.charset = config["charset"]
        self.con = None
        self.cursor = None

    def create_con(self):
        """
        创建连接
        """
        try:
            self.con = pymysql.connect(host=self.host, port=self.port, user=self.user, password=self.password,
                                       database=self.db, charset='utf8')
            self.cursor = self.con.cursor()
            return True
        except Exception as e:
            print(e)
            return False

    #
    def close_con(self):
        """
        关闭链接
        """
        if self.cursor:
            self.cursor.close()
        if self.con:
            self.con.close()

    # sql执行
    def execute_sql(self, sql):
        """
        执行插入/更新/删除语句
        """
        try:
            self.create_con()
            print(sql)
            self.cursor.execute(sql)
            self.con.commit()
        except Exception as e:
            print(e)
        finally:
            self.close_con()

    def select(self, sql, *args):
        """
        执行查询语句
        """
        try:
            self.create_con()
            print(sql)
            self.cursor.execute(sql, args)
            res = self.cursor.fetchall()
            return res
        except Exception as e:
            print(e)
            return False
        finally:
            self.close_con()

config = {
    "host": 'localhost',
    "port": 3306,
    "user": 'root',
    "password": '123456',
    "db": 'test',
    "charset": 'utf8'
}
db = MysqlHelper(config)
db.execute_sql("insert into user (username, password) values ('username4','password4')")
db.select("SELECT * FROM user;")