Python学习笔记-数据库操作

主要是通过python的DBUtils库、MySQLdb库来实现连接池操作数据库

import MySQLdb    
    
from DBUtils.PooledDB import PooledDB    
    
class DBHelper(object):    
        
    __pool = None    
        
    def __init__(self):    
        self._conn = DBHelper.__getConnection()    
        self._cursor = self._conn.cursor()    
   
    @staticmethod    
    def __getConnection():    
        if DBHelper.__pool is None :    
            __pool = PooledDB(creator = MySQLdb,    
                              mincached=1,    
                              maxcached=20,    
                              host = '127.0.0.1',    
                              port = 3306,    
                              user = 'root',    
                              passwd = '123456',    
                              db = 'test')    
            
        return __pool.connection()    
    
    def execute(self, sql, parameter=None):    
        if parameter is None:    
            self._cursor.execute(sql)    
        else :    
            self._cursor.execute(sql, parameter)    
            
    def readOne(self, sql, parameter=None):    
        if parameter is None :    
            count = self._cursor.execute(sql)    
        else :    
            count = self._cursor.execute(sql, parameter)    
        if count > 0:    
            return self._cursor.fetchone()    
        else :    
            return None    
            
    def readList(self, sql, parameter=None):    
        if parameter is None :    
            count = self._cursor.execute(sql)    
        else :    
            count = self._cursor.execute(sql, parameter)    
        if count > 0:    
            return self._cursor.fetchall()    
        else :    
            return None    
            
    def commint(self):    
        self._conn.commit()    
            
    def close(self):    
        if self._cursor :    
            self._cursor.close()    
        if self._conn :    
            self._conn.close()