Python实现一个简单的MySQL类

#!/usr/bin/env python
# -*- coding:utf-8 -*-
# Created on 2011-2-19
# @author: xiaoxiao
import MySQLdb
import sys
__all__ = ['MySQL']
class MySQL(object):
    '''
    MySQL
    '''
    conn = ''
    cursor = ''
    def __init__(self,host='localhost',user='root',passwd='root',db='mysql',charset='utf8'):
      
        """MySQL Database initialization """
        try:
            self.conn = MySQLdb.connect(host,user,passwd,db)
        except MySQLdb.Error,e:
            errormsg = 'Cannot connect to server\nERROR (%s): %s' %(e.args[0],e.args[1])
            print errormsg
            sys.exit()
          
        self.cursor = self.conn.cursor()
      
    def query(self,sql):
        """  Execute SQL statement """
        return self.cursor.execute(sql)
  
    def show(self):
        """ Return the results after executing SQL statement """
        return self.cursor.fetchall()
             
    def __del__(self):
        """ Terminate the connection """
        self.conn.close()
        self.cursor.close()
      
#test
if __name__ == '__main__':
  
    mysql = MySQL(host=localhost,passwd='test',db='mysql')
    mysql.query('select * from users')
    result = mysql.show()
    print len(result)
    print result[1]