def insertRuleset(self, ruleset, domain):
		'''增加一个robots.txt规则集'''
		cur = self.conn.cursor()
		cur.execute("SELECT did FROM Domains WHERE domain=?", (domain,))
		did = cur.fetchone()[0]
		cur.execute("INSERT INTO Rulesets VALUES (NULL,?,?)",(did, ruleset))
		# 写入到文件
		self.conn.commit()
def connect ():
    '''
    Create the connection to the MongoDB and create 3 collections needed
    '''
    try:
        # Create the connection to the local host 
        conn = pymongo.MongoClient()
        print 'MongoDB Connection Successful'
    except pymongo.errors.ConnectionFailure, err:
        print 'MongoDB Connection Unsuccessful'
        return False