MapReduce ( or a simply Map ) gets really slow when database has a
significant amount of data ( or distributed over several servers ). Get
instead is always faster as Riak doesn't have to search for the key (
you tell Riak exactly where to GET the data in your url )
Rohman
On
Thu, 28 Jul 2011 23:43:06 +0400, m...@mawhrin.net wrote:
> Hi,
>
> (I
looked at various places for the information, however I could not
> find
anything that would answer the question. It's not completely ruled
> out
that not all places were checked though :))
>
> I use PB erlang
interface to access the database. Given a bucket name
> and a key, the
value can easily be extracted using:
>
> {ok, Object} =
riakc_pb_socket:get(Conn, Bucket, Key),
> Value =
riakc_obj:get_value(Object)
>
> Alternatively, a mapred (actually, just
map) request could be issued:
>
> {ok, [{_, Value}]} =
riakc_pb_socket:mapred(Conn, [
> {Bucket, Key}
> ], [
> {map, {modfun,
riak_kv, map_object_value}, none, true}
> ])
>
> I would expect that
the result is the same while in the second case, the
> amount of data
transferred to the client is smaller (which might be good
> for certain
situations).
>
> So the [open] question is: are there any reasons for
using the first
> approach over the second?
>
> --
> Misha
--
[1]
ANTONIO ROHMAN FERNANDEZ
CEO, Founder & Lead
Engineer
roh...@mahalostudio.com [2]
PROJECTS
MaruBatsu.es
[3]
PupCloud.com [4]
Wedding Album [5]
Links:
------
[1]
http://mahalostudio.com
[2] mailto:roh...@mahalostudio.com
[3]
http://marubatsu.es
[4] http://pupcloud.com
[5]
http://wedding.mahalostudio.com
_______________________________________________
riak-users mailing list
riak-users@lists.basho.com
http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com
