python封装数据库

https://blog.csdn.net/the_lone_wolfs/article/details/79079257
1.数据库配置

#db.conf
#配置数据库
[database]
dbhost=127.0.0.1
dbport=3366
dbname=test
dbuser=test
dbpassword=test
dbcharset=utf8

2.读取配置

import ConfigParser
import os

#获取config配置文件
def getConfig(section, key):
    config = ConfigParser.ConfigParser()
    path = os.path.split(os.path.realpath(__file__))[0] + '\db.conf' # linux /
    config.read(path)
    return config.get(section, key)

3.链接数据库

# encoding:utf-8
# name:mod_db.py
'''
使用方法：1.在主程序中先实例化DB Mysql数据库操作类。
      2.使用方法:db=database()  db.fetch_all("sql")
'''
import MySQLdb
import MySQLdb.cursors
import mod_config
import mod_logger

DB = "database"
LOGPATH = mod_config.getConfig('path', 'logpath') + 'database.log'
DBNAME = mod_config.getConfig(DB, 'dbname')
DBHOST = mod_config.getConfig(DB, 'dbhost')
DBUSER = mod_config.getConfig(DB, 'dbuser')
DBPWD = mod_config.getConfig(DB, 'dbpassword')
DBCHARSET = mod_config.getConfig(DB, 'dbcharset')
DBPORT = mod_config.getConfig(DB, "dbport")
logger = mod_logger


# 数据库操作类
class database:
    # 注，python的self等于其它语言的this
    def __init__(self, dbname=None, dbhost=None):
        self._logger = logger
        # 这里的None相当于其它语言的NULL
        if dbname is None:
            self._dbname = DBNAME
        else:
            self._dbname = dbname
        if dbhost is None:
            self._dbhost = DBHOST
        else:
            self._dbhost = dbhost

        self._dbuser = DBUSER
        self._dbpassword = DBPWD
        self._dbcharset = DBCHARSET
        self._dbport = int(DBPORT)
        self._conn = self.connectMySQL()

        if (self._conn):
            self._cursor = self._conn.cursor()

    # 数据库连接
    def connectMySQL(self):
        conn = False
        try:
            conn = MySQLdb.connect(host=self._dbhost,
                                   user=self._dbuser,
                                   passwd=self._dbpassword,
                                   db=self._dbname,
                                   port=self._dbport,
                                   cursorclass=MySQLdb.cursors.DictCursor,
                                   charset=self._dbcharset,
                                   )
            cursor = conn.cursor()

        except Exception, data:
            self._logger.error("connect database failed, %s" % data)
            conn = False
        return conn

    # 获取查询结果集
    def fetch_all(self, sql):
        res = ''
        if (self._conn):
            try:
                self._cursor.execute(sql)
                res = self._cursor.fetchall()
            except Exception, data:
                res = False
                logger.warn("query database exception, %s" % data)
        return res

    def update(self, sql):
        flag = False
        if (self._conn):
            try:
                self._cursor.execute(sql)
                self._conn.commit()
                flag = True
            except Exception, data:
                flag = False
              logger.warn("update database exception, %s" % data)

        return flag
   #更新数据库中表的某几列：update login set result =%s;eg:sql='insert into pythontest values(%s,%s,%s,now()',params=(6,'C#','good book') 
    def updateByParams(self, sql, params):
        flag = False
        if (self._conn):
            try:
                self._cursor.execute(sql,params)
                self._conn.commit()
                flag = True
            except mdb.Error as data:
                flag = False
                logger.warn("update database by params exception, %s" % data)
            finally:
                self.close()
        return flag


    # 关闭数据库连接
    def close(self):
        if (self._conn):
            try:
                if (type(self._cursor) == 'object'):
                    self._cursor.close()
                if (type(self._conn) == 'object'):
                    self._conn.close()
            except Exception, data:
                logger.warn("close database exception, %s,%s,%s" % (data, type(self._cursor), type(self._conn)))