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From: Jason Yang <lin.yang.jason@gmail.com>
Date: Tue, 11 Sep 2012 11:33:02 +0800
Message-ID: 
 <CAE636z8E606w16qZv9Zj3D3vA-rtrMQY9AJhD8esJKdLqnkzcA@mail.gmail.com>
Subject: How to make different mappers execute different processing on a same
 data ?
To: user@hadoop.apache.org
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Hi, all

I've got a question about how to make different mappers execute different
processing on a same data?

Here is my scenario:
I got to process a data, however, there multiple choices to process this
data and I have no idea which one is better, so I was thinking that maybe I
could execute multiple mappers, in which different processing solution is
applied, and eventually the best one is chosen according to some evaluation
functions.

But I'm not sure whether this could be done in MapReduce.

Any help would be appreciated.

-- 
YANG, Lin

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Content-Type: text/html; charset=ISO-8859-1
Content-Transfer-Encoding: quoted-printable

<div><span style=3D"color:rgb(34,34,34);font-family:arial,sans-serif;font-s=
ize:15px;background-color:rgb(255,255,255)">Hi, all</span><div style=3D"col=
or:rgb(34,34,34);font-family:arial,sans-serif;font-size:15px;background-col=
or:rgb(255,255,255)">

<br></div><div style=3D"color:rgb(34,34,34);font-family:arial,sans-serif;fo=
nt-size:15px;background-color:rgb(255,255,255)">I&#39;ve got a question abo=
ut how to make different mappers execute different processing on a same dat=
a?=A0</div>

<div style=3D"color:rgb(34,34,34);font-family:arial,sans-serif;font-size:15=
px;background-color:rgb(255,255,255)"><br></div><div style=3D"color:rgb(34,=
34,34);font-family:arial,sans-serif;font-size:15px;background-color:rgb(255=
,255,255)">

Here is my scenario:</div><div style=3D"color:rgb(34,34,34);font-family:ari=
al,sans-serif;font-size:15px;background-color:rgb(255,255,255)">I got to pr=
ocess a data, however, there multiple choices to process this data and I ha=
ve no idea which one is better, so I was thinking that maybe I could execut=
e multiple mappers, in which different processing solution is applied, and =
eventually the best one is chosen according to some evaluation functions.</=
div>

<div style=3D"color:rgb(34,34,34);font-family:arial,sans-serif;font-size:15=
px;background-color:rgb(255,255,255)"><br></div><div style=3D"color:rgb(34,=
34,34);font-family:arial,sans-serif;font-size:15px;background-color:rgb(255=
,255,255)">

But I&#39;m not sure whether this could be done in MapReduce.</div><div sty=
le=3D"color:rgb(34,34,34);font-family:arial,sans-serif;font-size:15px;backg=
round-color:rgb(255,255,255)"><br></div><div style=3D"color:rgb(34,34,34);f=
ont-family:arial,sans-serif;font-size:15px;background-color:rgb(255,255,255=
)">

Any help would be appreciated.</div></div><br>-- <br><div>YANG, Lin</div><b=
r>

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