python连接mysql数据库类

dbhelper.py：

import pymysql
import logging
import sys
from mysql.db_config import db_config

# 加入日志
# 获取logger实例
logger = logging.getlogger("basespider")
# 指定输出格式
formatter = logging.formatter('%(asctime)s\
              %(levelname)-8s:%(message)s')
# 文件日志
file_handler = logging.filehandler("operation_database.log")
file_handler.setformatter(formatter)
# 控制台日志
console_handler = logging.streamhandler(sys.stdout)
console_handler.setformatter(formatter)

# 为logge添加具体的日志处理器
logger.addhandler(file_handler)
logger.addhandler(console_handler)

logger.setlevel(logging.info)


class dbhelper():
    # 构造函数,初始化数据库连接
    def __init__(self,sql,params=none):
        self.sql = sql
        self.params = params
        self.conn = none
        self.cur = none

    def connectiondatabase(self):
        print(db_config['host'],db_config['username'],db_config['password'],db_config['database'],db_config['charset'])
        try:
            self.conn = pymysql.connect(db_config['host'],db_config['username'],
                                    db_config['password'],db_config['database'],charset=db_config['charset'])
        except:
            logger.error("connectdatabase failed")
            return false
        self.cur = self.conn.cursor()
        return true



    # 关闭数据库
    def closedatabase(self):
        # 如果数据打开，则关闭；否则没有操作
        if self.conn and self.cur:
            self.cur.close()
            self.conn.close()
        return true

    # 执行数据库的sq语句,主要用来做插入操作
    def execute(self):
        self.connectiondatabase()
        try:
            if self.conn and self.cur:
                # 正常逻辑，执行sql，提交操作
                self.cur.execute(self.sql,self.params)
                self.conn.commit()
        except:
            logger.error("execute failed: " + self.sql)
            logger.error("params: " + self.params)
            self.closedatabase()
            return false
        return true

    # 用来查询表数据
    def select(self):
        self.connectiondatabase()
        self.cur.execute(self.sql,self.params)
        result = self.cur.fetchall()
        print(result)
        return result

配置信息 db_config.py

 

db_config = {
    'host':'127.0.0.1',
    'port':3306,
    'username':'root',
    'password':'admin',
    'database':'database',
    'charset':'utf8'
}

 测试代码：

from mysql import  dbhelper as mdb


def main():
    # 连接 mysql，获取连接的对象
    sql=r'select * from tusers'
    db=mdb.dbhelper(sql)
    rows=db.select()
    # 依次遍历结果集，发现每个元素，就是表中的一条记录，用一个元组来显示
    for row in rows:
        print(row)


if __name__ == '__main__':
    main()