GAE Python数据存储查询

Question

进出口新的GAE和python太，我尝试使用的数据存储在脚本如下

from google.appengine.ext import db 
from google.appengine.ext import webapp 
from google.appengine.ext.webapp import util 

class Pincodes(db.Model): 
    city = db.StringProperty() 
    code = db.StringProperty() 

class MainHandler(webapp.RequestHandler): 
    def get(self): 
    q = Pincodes.all() 
    q = q.filter("city =", "some_city") 
    p = q.get() 
    r = 'city: %s code: %s' % (pincode.city, pincode.code) 
    self.response.out.write(r)  

我的剧本还含有常用的高清main（）和if__name构建简单的应用程序，即时通讯发展它从code.google文档中显示简单的Hello World应用程序一步一步，它工作正常，我hav上传包含10条记录本地数据存储示范pincode数据和它的罚款，但我不能够查询和显示它在网页上我试图自我.response.out.write和输出是“city：code：”而不是“city：mumbai code：400001”我的脚本有什么问题

Answer 1

use

entity = q.get() # use get if you want one entity only 
r = 'city: %s code: %s' %(entity.city, entity.code) 
self.response.out.write(r) 

，而不是打印

编辑：

def get(self): 
    q = Pincodes.all() 
    q = q.filter("city =", "some_city") 
    entity = q.get() # use get if you want one entity only 
    r = 'city: %s code: %s' %(entity.city, entity.code) 
    self.response.out.write(r) 

EDIT2：

def get(self): 
    q = Pincodes.all() 
    q = q.filter("city =", "some_city") 
    entity = q.get() # use get if you want one entity only 
    if not entity: 
     self.response.out.write('sorry no entities found') 
    else: 
     r = 'city: %s code: %s' %(entity.city, entity.code) 
     self.response.out.write(r)