Emulating composite index queries with secondary indexes and key filters

Jeremiah Peschka jeremiah.peschka at gmail.com
Tue Aug 28 07:51:52 EDT 2012


As best as I can recall, you can't key filter on 2i. You can, however,
perform range filtering. You could query where the 2i key is between
20110101T00:00:00Z|a|a and 20110201T00:00:00Z|zzz|zzz

Please forgive any typos. I'm using a phone.

On Tuesday, August 28, 2012, Olav Frengstad wrote:

> Hey,
>
> I'm looking to use riak to store time series. So naturaly i'm in the
> processes of validating all possible methods this query. A object
> has a id, origin, timestamp and type. The query in question is to
> select all object within a time range that originated from "origin"
> and has a certain "type".
>
> The current plan is to store the timestamp as a secondary index and
> then have composite keys responsible for matching origin/type predicate.
>
> A key would look like this: "<id>:<origin>:<type>".
>
> To query one would just pipe the 2i query to key filter map reduce:
>
> curl -X POST -H "Content-Type: application/json" -d '{"inputs":{
> "bucket" : "seriesx", "index" : "timestamp_int", "start" : 123,
> "end" : 456, "key_filters" : [["ends_with", "<origin>:<type>"]]}}'
>
> In regards to this "imaginary" solution i have a few questions:
>   1) is this possible, or does key filter only work on a bucket?
>   2) Would this be a efficient solution, considering the 2i query
>      will return 10k+ results? the reduce should cut that in half.
>   3) What other options to i have for querying this? Obviously i can
>      use Riak search, but the term based indexing puts me off. Other
>      option is building this manually with empty object just linking.
>
> --
> Med Vennlig Hilsen
> Olav Frengstad
>
> Systemutvikler // FWT
> +47 920 42 090
>
> _______________________________________________
> riak-users mailing list
> riak-users at lists.basho.com <javascript:;>
> http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com
>


-- 
---
Jeremiah Peschka
Managing Director, Brent Ozar PLF, LLC
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.basho.com/pipermail/riak-users_lists.basho.com/attachments/20120828/8f301445/attachment.html>


More information about the riak-users mailing list