问题描述
我已经看到下面的链接,它是使用 python 开始 mapreduce 的链接
I have seen the below link which is of getting started mapreduce with python
http://code.google.com/p/appengine-mapreduce/wiki/GettingStartedInPython
但我仍然无法理解它是如何工作的.我正在执行下面的代码,但无法理解到底发生了什么?
But still I am not able to understand how its working. I am executing below code but not able to understand what exactly is happening?
ma??preduce.yaml
mapreduce: - name: Testmapper mapper: input_reader: mapreduce.input_readers.DatastoreInputReader handler: main.process params: - name: entity_kind default: main.userDetail
ma??preduce/main.py
some code class userDetail(db.Model): name = db.StringProperty() some code def process(u): u.name="mahesh" yield op.db.Put(u)
我正在执行此操作,它在状态页面中为我提供了 status = success.
I am executing this and it gives me status = success in status page.
但无法理解发生了什么
我想用 mapreduce 做的主要事情是从实体中搜索或计算记录
The main thing I want do with mapreduce is to search or count records from entity
那么任何人都可以帮助我吗??
So anyone can please help me??
提前致谢
推荐答案
您正在将 "mahesh" 值设置为所有 userDetail 的 StringProperty name 实体.
You are setting the "mahesh" value to the StringProperty name of all your userDetail entities.
如果您想计算您的实体,请使用:
If you want to count your entities use :
from mapreduce import operation as op def process(entity): yield op.counters.Increment("counter1")