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From Sameer Kalburgi <sameerkalbu...@gmail.com>
Subject Re: UDF of processing a column like pig?
Date Tue, 29 Mar 2011 02:22:52 GMT
Somewhat unrelated, but is there any info/docs on how much overhead using a
UDF adds to the map jobs?

On Mon, Mar 28, 2011 at 3:48 PM, Edward Capriolo <edlinuxguru@gmail.com>wrote:

> On Mon, Mar 28, 2011 at 2:45 PM, Christopher, Pat
> <patrick.christopher@hp.com> wrote:
> > I think so.  I haven’t looked for a non-java API though.
> >
> >
> >
> > Pat
> >
> >
> >
> > From: Michael Jiang [mailto:it.mjjiang@gmail.com]
> > Sent: Monday, March 28, 2011 11:31 AM
> > To: user@hive.apache.org
> > Cc: Christopher, Pat
> > Subject: Re: UDF of processing a column like pig?
> >
> >
> >
> > Thanks, so, I guess only java is supported, right?
> >
> > On Mon, Mar 28, 2011 at 11:27 AM, Christopher, Pat
> > <patrick.christopher@hp.com> wrote:
> >
> > You can create UDFs, UDAFs and UDTFs.
> > http://wiki.apache.org/hadoop/Hive/HivePlugins
> >
> >
> >
> > Pat
> >
> >
> >
> > From: Michael Jiang [mailto:it.mjjiang@gmail.com]
> > Sent: Monday, March 28, 2011 11:13 AM
> > To: user@hive.apache.org
> > Subject: UDF of processing a column like pig?
> >
> >
> >
> > I want to have a function that returns the hour information from a date
> > string (wiz not a known format supported by current date functions, but
> > basically this is just a use case example). In pig, you can create a UDF
> > (user defined function) and apply it to a column. Is there an equivalent
> > thing in Hive? I know I can write a mapper to take whole line and
> transform
> > the specific column I want. But it's not convenient because you have to
> > duplicate the same code for each different source table.
> >
> > Thanks!
> >
> >
>
> Hive is written in Java. Thus UDF's are written in java. If you want
> to use a language outside of Java you need to use streaming.
>
> http://wiki.apache.org/hadoop/Hive/LanguageManual/Transform
>
> (but why would you want to since Java is the rockstar of all languages?)
>

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