hbase-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Ted Yu <yuzhih...@gmail.com>
Subject Re: transactional hbase
Date Sun, 18 Jul 2010 20:21:01 GMT
If only a subset of the child entities needs update, it is not trivial to
maintain consistency across multiple writers.

On Fri, Jul 16, 2010 at 2:24 AM, Cosmin Lehene <clehene@adobe.com> wrote:

> Hi,
>
> HBase supports row-level atomic operations. If you need to update more than
> a row in a single transaction you'll have to use a coordination mechanism.
> You can use Zookeeper for that.
>
> However you can also evaluate whether you can't use a single table for your
> operation by taking advantage of the columnar model. Basically you can
> encode an entire star schema in a single table in HBase. Each family can act
> as a table. So when you have  1-M relations you can just write all the
> values (M) in a single row (1). This way you could use a single put
> operation to update your "child" entities.
>
> Cosmin
>
> On Jul 16, 2010, at 12:57 AM, N Kapshoo wrote:
>
> > Can someone please point me to some more info? I am concerned about
> > inconsistent data and am evaluating risk...
> > Thanks.
> >
> > On Thu, Jul 15, 2010 at 3:11 PM, N Kapshoo <nkapshoo@gmail.com> wrote:
> >> Hi,
> >>
> >> I have a write API call that does 3 puts (2 puts  to one table and a
> >> 3rd put to a second table). How do I go about making sure that these
> >> all happen or none happen at all?  In short, an atomic transaction.
> >>
> >> I read up a little bit about the TransactionManager and that I need to
> >> modify hbase-site.xml to make these TransactionalRegion Servers. Can
> >> someone point me to some more info about the same? What versions, what
> >> performance impacts etc? Are there some good urls that anyone can
> >> share?
> >>
> >> I am using HBase 0.20.3 at this time. I dont believe transactions are
> >> supported in this version. If I were to go live and then decide to use
> >> transactions later, how should I plan on an upgrade?
> >>
> >> Thanks.
> >>
>
>

Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message