Hi,
thanks for your repsonse. I had a look at both Esper and Siddhi. Please
correct me if I'm wrong, but I don't think these fit my purpose: Both
use a SQL-Like query language, right?
What I am aiming at, is to visually define a query (consider for example
the heartbeat [1]) and then compute the distance between the query and
some datastream (for each new datapoint). But I cannot define such a
complex query using this SQL-like query language!? Or did I miss something?
Johannes
[1] http://en.wikipedia.org/wiki/Electrocardiography#Waves_and_intervals
On 11/11/2014 08:16 AM, Sajith wrote:
Hi Johannes,
You can also use Sidddhi complex event processing engine to achieve
your tasks. [1] is a bolt I wrote using Siddhi.
[1]
https://github.com/sajithshn/siddhi-storm/blob/master/src/main/java/org/wso2/siddhi/storm/component/SiddhiBolt.java
On Tue, Nov 11, 2014 at 1:29 AM, Manoj Jaiswal
<[email protected] <mailto:[email protected]>> wrote:
Hi Johannes,
We are doing something similar using Esper in storm.
The queries are set in EsperBolt and realtime data is processed
through that.
-Manoj
On Mon, Nov 10, 2014 at 3:54 AM, Klausen Schaefersinho
<[email protected] <mailto:[email protected]>> wrote:
Hi,
> The main reason I write this mail is, because I have to
access the last N elements of each stream for each new
arriving element
You can not go back in a stream, so you have to write your own
bolt that stores the last windows. That should be pretty
straight forward.
On Mon, Nov 10, 2014 at 12:26 PM, Johannes Hugo Kitschke
<[email protected]
<mailto:[email protected]>> wrote:
Hi there,
I want to solve a task and wonder if Storm is suitable for
this. My task:
- input (many) numerical datastreams (e.g. stock
market data, seismic data, ...)
- define (many) queries of length N (may be different
for each query)
- compute distance (e.g. using dynamic time warping)
between each query and the last N datapoints of each
datastream
- report matches if distance < eps
This is a rough outline. I am completely new to Storm and
I wonder, if Storm is a good candidate to solve this
problem (if not, alternatives?). The main reason I write
this mail is, because I have to access the last N elements
of each stream for each new arriving element. But every
example I found does only do some computation on one
element at a time.
While writing this, I came across the**'RollingCountBolt'.
Does this implement the functionality I want? Does this
mean each Bolt doing the distance computation for the last
N points has to store these points?
I would be interested in your thoughts, hints and idea**s.
Thanks!
Johannes
