accumulo-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Christopher <ctubb...@apache.org>
Subject Re: Trigger for Accumulo table
Date Thu, 03 Dec 2015 05:17:29 GMT
You could also implement a constraint to notify an external system when a
row is updated.

On Wed, Dec 2, 2015, 22:54 Josh Elser <josh.elser@gmail.com> wrote:

> oops :)
>
> [1] http://fluo.io/
>
> Josh Elser wrote:
> > Hi Thai,
> >
> > There is no out-of-the-box feature provided with Accumulo that does what
> > you're asking for. Accumulo doesn't provide any functionality to push
> > notifications to other systems. You could potentially maintain other
> > tables/columns in which you maintain the last time a row was updated,
> > but the onus is on your "other services" to read the table to find out
> > when a change occurred (which is probably not scalable at "real time").
> >
> > There are other systems you could likely leverage to solve this,
> > depending on the durability and scalability that your application needs.
> >
> > For a system "close" to Accumulo, you could take a look at Fluo [1]
> > which is an implementation of Google's "Percolator" system. This is a
> > system based on throughput rather than low-latency, so it may not be a
> > good fit for your needs. There are probably other systems in the Apache
> > ecosystem (Kafka, Storm, Flink or Spark Streaming maybe?) that are be
> > helpful to your problem. I'm not an expert on these to recommend on (nor
> > do I think I understand your entire architecture well enough).
> >
> > Thai Ngo wrote:
> >> Hi list,
> >>
> >> I have a use-case when existing rows in a table will be updated by an
> >> internal service. Data in a row of this table is composed of 2 parts:
> >> 1st part - immutable and the 2nd one - will be updated (filled in) a
> >> little later.
> >>
> >> Currently, I have a need of knowing when and which rows will be updated
> >> in the table so that other services will be wisely start consuming the
> >> data. It will make more sense when I need to consume the data in near
> >> realtime. So developing a notification function or simpler - a trigger
> >> is what I really want to do now.
> >>
> >> I am curious to know if someone has done similar job or there are
> >> features or APIs or best practices available for Accumulo so far. I'm
> >> thinking of letting the internal service which updates the data notify
> >> us whenever it updates the data.
> >>
> >> What do you think?
> >>
> >> Thanks,
> >> Thai
>

Mime
View raw message