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Posted to mapreduce-user@hadoop.apache.org by unmesha sreeveni <un...@gmail.com> on 2014/01/11 19:45:11 UTC
Expressions in MapReduce
Are we able to do expresions in Mapreduce
Say if i am having a csv file . which has 2 columns.
The user is giving an expresion
col1 + col2 = col3
Are we able to do this?
And when again the user wants col1 - col2 = col4
Can we do it in the same mapreduce (dynamic change of expressions)
--
*Thanks & Regards*
Unmesha Sreeveni U.B
Junior Developer
http://www.unmeshasreeveni.blogspot.in/
Re: Expressions in MapReduce
Posted by Marco Shaw <ma...@gmail.com>.
I'm not sure on your exact details, but it is always possible to do just
about anything with your MR logic.
Now, to suggests that there may or may not be a performance hit is a
different story...
Marco
On Sat, Jan 11, 2014 at 2:45 PM, unmesha sreeveni <un...@gmail.com>wrote:
> Are we able to do expresions in Mapreduce
> Say if i am having a csv file . which has 2 columns.
> The user is giving an expresion
> col1 + col2 = col3
> Are we able to do this?
> And when again the user wants col1 - col2 = col4
> Can we do it in the same mapreduce (dynamic change of expressions)
>
> --
> *Thanks & Regards*
>
> Unmesha Sreeveni U.B
> Junior Developer
>
> http://www.unmeshasreeveni.blogspot.in/
>
>
>
Re: Expressions in MapReduce
Posted by Marco Shaw <ma...@gmail.com>.
I'm not sure on your exact details, but it is always possible to do just
about anything with your MR logic.
Now, to suggests that there may or may not be a performance hit is a
different story...
Marco
On Sat, Jan 11, 2014 at 2:45 PM, unmesha sreeveni <un...@gmail.com>wrote:
> Are we able to do expresions in Mapreduce
> Say if i am having a csv file . which has 2 columns.
> The user is giving an expresion
> col1 + col2 = col3
> Are we able to do this?
> And when again the user wants col1 - col2 = col4
> Can we do it in the same mapreduce (dynamic change of expressions)
>
> --
> *Thanks & Regards*
>
> Unmesha Sreeveni U.B
> Junior Developer
>
> http://www.unmeshasreeveni.blogspot.in/
>
>
>
Re: Expressions in MapReduce
Posted by Marco Shaw <ma...@gmail.com>.
I'm not sure on your exact details, but it is always possible to do just
about anything with your MR logic.
Now, to suggests that there may or may not be a performance hit is a
different story...
Marco
On Sat, Jan 11, 2014 at 2:45 PM, unmesha sreeveni <un...@gmail.com>wrote:
> Are we able to do expresions in Mapreduce
> Say if i am having a csv file . which has 2 columns.
> The user is giving an expresion
> col1 + col2 = col3
> Are we able to do this?
> And when again the user wants col1 - col2 = col4
> Can we do it in the same mapreduce (dynamic change of expressions)
>
> --
> *Thanks & Regards*
>
> Unmesha Sreeveni U.B
> Junior Developer
>
> http://www.unmeshasreeveni.blogspot.in/
>
>
>
Re: Expressions in MapReduce
Posted by Marco Shaw <ma...@gmail.com>.
I'm not sure on your exact details, but it is always possible to do just
about anything with your MR logic.
Now, to suggests that there may or may not be a performance hit is a
different story...
Marco
On Sat, Jan 11, 2014 at 2:45 PM, unmesha sreeveni <un...@gmail.com>wrote:
> Are we able to do expresions in Mapreduce
> Say if i am having a csv file . which has 2 columns.
> The user is giving an expresion
> col1 + col2 = col3
> Are we able to do this?
> And when again the user wants col1 - col2 = col4
> Can we do it in the same mapreduce (dynamic change of expressions)
>
> --
> *Thanks & Regards*
>
> Unmesha Sreeveni U.B
> Junior Developer
>
> http://www.unmeshasreeveni.blogspot.in/
>
>
>