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From Saravana Kumar <saravana.had...@gmail.com>
Subject Re: Derby with Hadoop --Why?
Date Wed, 10 Aug 2011 05:37:09 GMT
Thanks For the Explanation but needs some clarity as well

Do you mean to say all the Information required to run a map/reduce job is
effectively stored in derby. It means hadoop(not Ecosystem) uses Derby?

On Tue, Aug 9, 2011 at 5:52 PM, Michael Segel <michael_segel@hotmail.com>wrote:

>
> Derby?
>
> First a little history...
> Derby started out long ago as Cloudscape. Cloudscape was bought by
> Informix. Informix was bought by IBM. IBM didn't understand Cloudscape and
> decided to open source the project under APL. Hence Derby was born.
>
> Derby is an excellent lightweight 100% java database. So when you have a
> Java framework, using Derby makes a lot of sense. Derby is used to persist
> some environment information and I believe its used in part of some of the
> unit testing.
>
> Where Derby has been replaced by MySQL is when someone wanted a multi-user
> database and they were more comfortable with MySQL than they were with
> Derby. (Hint: Derby can be started as an embedded single user database, or
> as a multi-user database by changing its invocation at startup. ;-)
>
> So I would guess the initial reason to go with Derby was that its released
> under APL and there were no licensing issues. ;-)
>
>
> > Date: Tue, 9 Aug 2011 15:17:35 +0530
> > Subject: Derby with Hadoop --Why?
> > From: saravana.hadoop@gmail.com
> > To: general@hadoop.apache.org
>  >
> > Hi
> >
> > What is the significance of Derby in Hadoop Project.
> > Why people are using Derby along with Hadoop
> >
> > Regards
> > Saravana Kumar.J
>
>

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