Re: Is a RDBMS needed?

From: Thomas Roach <>
Date: Thu, 30 Jun 2011 10:49:46 -0400
Message-ID: <>

Cassandra is really cool technology. When "IT" works. I can't tell you how many times twitter, reddit, even facebook have issues. I guess downtime is sexy! :)

I do go into the IRC Cassandra channel. It is funny seeing the developers trying to use it ask questions and see the answers.

What if I need to get the top n number of records and then sort based on this? (You can't do that)

..... No we don't support that.
.... Not possible at this time.
..... That is a bug and we will get that fixed when we get around to it, we
have real jobs that pay the bills...
... Just fix it yourself, it's open source. .... Why would you want to do that? Use an RDBMS for that...

Goes on and on.

I also recently saw that Yahoo spun off a Hadoop company. They predicted that in 5 years, 50% of all data will be stored on Hadoop. I think a lot of people don't know what NoSQL and Hadoop really are. They just see them as the latest silver bullet (buzzwords). Ironically, on Apache's Hadoop site, I found this gem.

Some bullets from the site.

  1. Hadoop is not a substitute for a database
  2. Hadoop is not always the best algorithm
  3. Hadoop and MapReduce is not a place to learn Java programming. You should know Java before working with Hadoop. (SQL is easier than Java IMO).
  4. Hadoop is not an idea place to learn networking error messages. Know them before you even immerse yourself.
  5. Hadoop clusters are not a place to learn Unix/Linux commands and system administration.
  6. Hadoop FS is not a replacement for a SAN Based HA based Filesystem.
  7. HDFS is not a POSIX Filesystem.

While it is a promising tool and another tool in the toolshed, there are many things Hadoop is not... But if you listen to all the buzz lately, you have every company from IBM, EMC to many kinds of startups tooting Hadoops horn as if it is all these things that Hadoop clearly says they are not. I am sure we have all been hammered with "BIG DATA"

Some people/customers have already been burned. Just use it where it makes sense and not where it doesn't. Same thing goes for an RDBMS.



On Wed, Jun 29, 2011 at 4:41 PM, Blake Wilson <> wrote:

> To continue this wonderful story, our developers set up a conference call
> with our technical people to the some high ranking technical people for the
> application. I was informed that I was working with old information. The new
> version of the LMS application will actually use a database (Apache Derby,
> MYSQL, Postgres or finally Oracle). It will also be able to use Apache
> Cassandra. Cassandra is a NoSQL database. This seemed to be the preferred
> approach by their technical people, but at least I am not tied to it.
> The bottom line is that although the new version has been released, it is
> still going through major modifications and information is not readily found
> as to what it looks like this week or next month. Who know what it will look
> like when I finally have to go to it in a few years? Maybe, I will be
> retired by then.
> Thanks,
> Blake
> On 6/9/2011 12:46 PM, Blake Wilson wrote:
>> This is a future release that is just being developed to be released in
>> the next 3-5 years. It is an open source application developed by some of
>> the universities that use it. Some large universities throughout the world
>> are currently using and contributing to it, including the University of
>> Michigan, Indiana, Cornell, Stanford, Yale and Oxford, etc. So, it is not an
>> small time application. I am not so worried about the current release, but
>> the future of it. We are not currently using the application, but I am
>> worried about where it will be in 5 years and do we want to be there?
>> We certainly can save a few bucks on the Oracle licensing, but at what
>> cost? I am glad to here your concerns as well. And yes, I realize that we
>> are all DBA's and may be somewhat prejudiced, but I think there is a some
>> potential trouble here in a few years.
>> Thank you for you responses and ideas.
>> Blake
>> --
> --

Thomas Roach

Received on Thu Jun 30 2011 - 09:49:46 CDT

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