Oh, I do know it is not "see if one node can return the desired results" as each node will have different results for your client and you get results from the first node, then results from second node, etc. etc. (I remember having this discussion but for the life of me can't remember why it is sequentialŠ.it may just be the overload thing). Hopefully someone else will respond with a better answer.
Dean On 8/21/13 9:10 AM, "Kanwar Sangha" <kan...@mavenir.com> wrote: >Thanks Dean. Any reason why it is sequential ? It is to avoid loading all >the nodes and see if one node can return the desired results ? > > >-----Original Message----- >From: Hiller, Dean [mailto:dean.hil...@nrel.gov] >Sent: 21 August 2013 07:36 >To: user@cassandra.apache.org >Subject: Re: Secondary Index Question > >Yup, there are other types of indexing like that in PlayOrm which do it >differently so all nodes are not hit so it works better for instance if >you are partitioning your data and you query into just a single partition >so it doesn't put load on all the nodes. (of course, you have to have a >partition strategy to partition by say month with key being the timestamp >of begin of month or maybe you partition by account as you only query >into accounts). > >It is feasible to roll your own as well. (though you do need to worry >about eventual consistency here when rolling your own) > >Later, >Dean > >From: Kanwar Sangha <kan...@mavenir.com<mailto:kan...@mavenir.com>> >Reply-To: "user@cassandra.apache.org<mailto:user@cassandra.apache.org>" ><user@cassandra.apache.org<mailto:user@cassandra.apache.org>> >Date: Tuesday, August 20, 2013 6:57 PM >To: "user@cassandra.apache.org<mailto:user@cassandra.apache.org>" ><user@cassandra.apache.org<mailto:user@cassandra.apache.org>> >Subject: Secondary Index Question > >Hi - I was reading some blogs on implementation of secondary indexes in >Cassandra and they say that "the read requests are sent sequentially to >all the nodes" ? > >So if I have a query to fetch ALL records with the secondary index >filter, will the co-ordinator node send the requests to nodes one by one ? > >Thanks, >Kanwar >
