hbase-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Amandeep Khurana <ama...@gmail.com>
Subject Re: Some confusions about What HBase is and When to use it?
Date Tue, 04 Aug 2009 16:51:12 GMT
If you haven't already read it, read the Google Bigtable paper.

On 8/4/09, Onur AKTAS <onur.aktas@live.com> wrote:
>
> Thank you for your answers, i need to understand the concept by reading more
> documents & examples.
> It will be very helpful if anyone adds various examples (i don't mean the
> source codes) about the usage areas where HBase fits perfectly.
>
> Thanks again.
>
>> Date: Tue, 4 Aug 2009 12:25:16 +0100
>> Subject: Re: Some confusions about What HBase is and When to use it?
>> From: trsell@gmail.com
>> To: hbase-user@hadoop.apache.org
>>
>> Comments inline
>>
>> 2009/8/4 Onur AKTAS <onur.aktas@live.com>:
>> >
>> > I'm confused about the when to use HBase. (Sure I have read everything
>> > and every link on http://wiki.apache.org/hadoop/Hbase/FAQ)
>> > Its distributed (when used on Hadoop) and provides efficient database
>> > for "VERY LARGE" amounts of datas, thats ok.
>> >
>> > But as I come from RDBMS world, i want to learn what I can do with HBase
>> > and how it can affect the quality of my applications.
>> >
>> > For example, as I also see on "HBase Schema Design Case Studies"
>> > referenced by FAQ, "Case 4: user-friends", there is something like
>> > user: id
>> >         info: name
>> >         info: sex
>> >         info: age
>> >         friend: user_id1
>> >         friend: user_id2
>> > etc..
>>
>> It's possibly worth pointing out, that a userinfo table will quite
>> likely fit fine inside a relational db like postgres.
>>
>> >
>> > 1- Let me understand the concept, Is there anyway to delete user's id
>> > from all of his/her friends' friend column? There is no foreign key
>> > relation then this is the thing that we must handle programmatically?
>> >
>>
>> That's correct, there is no way to do this automatically, there are no
>> relations in HBase.
>>
>> > 2- Is it also useful when the data is small but the calculations on it
>> > is complex? For example, "calculating the degree of contacts" ?
>> >
>>
>> HBase 0.20 handles small cells fine, eg. I've loaded a 700 million
>> cell table of integers. You can run map reduce jobs over the whole
>> table if you want to do processing.
>>
>> > 3- Some high traffic applications like making Facebook's, twitter's live
>> > status feed with HBase is possible? (Distribution of feeds to friend
>> > lists etc.)
>> >
>>
>> I can't really answer that, as I haven't used it in this way. It has a
>> really good write throughput though. You could optimise for this case.
>> In memory tables etcetera. You'd want to not run any map reduce over
>> it at the same time.
>>
>> > Or
>> > Its main goal is to analyse whole data and calculations for the internal
>> > use? Not  for serving them to users in realtime like RDBMS?
>>
>> HBase 0.20 can handle real time now. See
>> http://devblog.streamy.com/2009/07/24/streamy-hadoop-summit-hbase-goes-realtime/
>>
>>
>> >
>> > Thank you so much.
>>
>>
>> hope that helps.
>> ~Tim
>
> _________________________________________________________________
> Windows Live tüm arkadaşlarınızla tek bir yerden iletişim kurmanıza yardımcı
> olur.
> http://www.microsoft.com/turkiye/windows/windowslive/products/social-network-connector.aspx


-- 


Amandeep Khurana
Computer Science Graduate Student
University of California, Santa Cruz

Mime
View raw message