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From: Mike Drob <mdrob@apache.org>
Date: Mon, 27 Apr 2015 12:27:51 -0500
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 <CAFAMeYLeJVeXT+LiEOWE-vxkc-q8HpBDdqKwkFcvD2ZtAR6=qg@mail.gmail.com>
Subject: Re: Approach to hold the output of an iterator in memory to do
 further operations
To: user@accumulo.apache.org
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Check out the MinCombiner

https://github.com/apache/accumulo/blob/master/core/src/main/java/org/apache/accumulo/core/iterators/user/MinCombiner.java

On Mon, Apr 27, 2015 at 12:19 PM, vaibhav thapliyal <
vaibhav.thapliyal.91@gmail.com> wrote:

> Hello everyone.
>
> I am trying to carry out max and min kind of operations using accumulo.
>
> But since the Accumulo iterators only operate on the entries that are
> lovally hosted I get the local max and local min of the instead of a global
> max and min.
>
> To get this global max and min, I have to calculate this client side.  I
> want to ask if there is some way to store this local max and min in memory
> using iterator. So that a global max and min can be calculated server side
> only.
>
> I tried to this by writing the result in another table and using another
> iterator to return me the global max and min.
>
> I want to ask if there if a way to store this in memory so as to avoid
> writing it to a table?
>
> Thanks
> Vaibhav
>

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<div dir=3D"ltr">Check out the MinCombiner<br><br><a href=3D"https://github=
.com/apache/accumulo/blob/master/core/src/main/java/org/apache/accumulo/cor=
e/iterators/user/MinCombiner.java">https://github.com/apache/accumulo/blob/=
master/core/src/main/java/org/apache/accumulo/core/iterators/user/MinCombin=
er.java</a><br></div><div class=3D"gmail_extra"><br><div class=3D"gmail_quo=
te">On Mon, Apr 27, 2015 at 12:19 PM, vaibhav thapliyal <span dir=3D"ltr">&=
lt;<a href=3D"mailto:vaibhav.thapliyal.91@gmail.com" target=3D"_blank">vaib=
hav.thapliyal.91@gmail.com</a>&gt;</span> wrote:<br><blockquote class=3D"gm=
ail_quote" style=3D"margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-le=
ft:1ex"><p dir=3D"ltr">Hello everyone. </p>
<p dir=3D"ltr">I am trying to carry out max and min kind of operations usin=
g accumulo. </p>
<p dir=3D"ltr">But since the Accumulo iterators only operate on the entries=
 that are lovally hosted I get the local max and local min of the instead o=
f a global max and min. </p>
<p dir=3D"ltr">To get this global max and min, I have to calculate this cli=
ent side.=C2=A0 I want to ask if there is some way to store this local max =
and min in memory using iterator. So that a global max and min can be calcu=
lated server side only. </p>
<p dir=3D"ltr">I tried to this by writing the result in another table and u=
sing another iterator to return me the global max and min. </p>
<p dir=3D"ltr">I want to ask if there if a way to store this in memory so a=
s to avoid writing it to a table? </p>
<p dir=3D"ltr">Thanks <br><span class=3D"HOEnZb"><font color=3D"#888888">
Vaibhav <br></font></span></p>
</blockquote></div><br></div>

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