Yes this is correct. But keep in mind Streaming Expression has a wide range of features that have nothing at all to do with the export handler. In general with Streaming Expressions you want to find the functions that get the job done using the least amount of work. The /export handler is often not the best choice. You'll want to read through the various streaming expressions to see if they might be more efficient for your use case.
Joel Bernstein http://joelsolr.blogspot.com/ On Mon, Oct 15, 2018 at 12:05 PM Kamal Kishore Aggarwal < kkroyal....@gmail.com> wrote: > Hi, > > After I performed the test on my data, I found out that direct /export and > streaming expression with export, both are giving almost same response > time. This was also pointed out by *Jan Høydahl* in his reply. > > Also, the documentation says export feature uses stream sorting technique > and streaming expression also uses steam technique. So, are they internally > works in same fashion. Please confirm. > > Regards > Kamal Kishore > > > > On Tue, Oct 2, 2018 at 5:51 PM Kamal Kishore Aggarwal < > kkroyal....@gmail.com> > wrote: > > > Hi, > > > > Thanks Jan & Joel. > > > > Though I will evaluate the performance over my data, but based on your > > experience, which one of the two is better in performance ?. Please > suggest > > > > Yeah, I know export does not get the data from all shards, but we can > > write code to aggregate the data from all shards. But only if export is > > better over stream. > > > > Thanks > > Kamal Kishore > > > > > > On Thu, Sep 27, 2018 at 11:04 PM Joel Bernstein <joels...@gmail.com> > > wrote: > > > >> The export handler does not do distributed search. So if you have a > >> multi-shard collection you may have to use Streaming Expressions to get > >> exports from all shards. > >> > >> > >> Joel Bernstein > >> http://joelsolr.blogspot.com/ > >> > >> > >> On Thu, Sep 27, 2018 at 4:32 AM Jan Høydahl <jan....@cominvent.com> > >> wrote: > >> > >> > Hi, > >> > > >> > Yes, you can choose which to use, it should give you about same > result. > >> > If you already work with the Solr search API it would be the easiest > for > >> > you to consume /export as you don't need to learn the new syntax and > >> parse > >> > the Tuple response. However, if you need to do stuff with the docs as > >> you > >> > stream them from Solr, then streaming expressions lets you enrich the > >> docs, > >> > modify, join etc on the fly. > >> > > >> > PS: When the /export docs says it uses a streaming tecnique, it does > NOT > >> > mean that it has uses the solr feature streaming expressions :) > >> > > >> > -- > >> > Jan Høydahl, search solution architect > >> > Cominvent AS - www.cominvent.com > >> > > >> > > 27. sep. 2018 kl. 09:07 skrev Kamal Kishore Aggarwal < > >> > kkroyal....@gmail.com>: > >> > > > >> > > Hi, > >> > > > >> > > I have a requirement to fetch all data from a collection. One way is > >> to > >> > use > >> > > streaming expression and other way is to use export. > >> > > > >> > > Streaming expression documentation says *streaming functions are > >> designed > >> > > to work with entire result sets rather then the top N results like > >> normal > >> > > search. This is supported by the /export handler.* > >> > > > >> > > Also, Export handler documentation says *this feature uses a stream > >> > sorting > >> > > technique that begins to send records within milliseconds and > >> continues > >> > to > >> > > stream results until the entire result set has been sorted and > >> exported.* > >> > > > >> > > These two statements concludes to me that for fetching entire > results > >> > > streaming expressions uses export handler and export handler uses > >> stream, > >> > > so, whether I use streaming expression or export handler, they are > >> > > internally same and would have same performance. I am correct over > >> here > >> > to > >> > > say so ? > >> > > > >> > > > >> > > Ref Links: > >> > > > >> > > https://lucene.apache.org/solr/guide/6_6/streaming-expressions.html > >> > > https://lucene.apache.org/solr/guide/6_6/exporting-result-sets.html > >> > > > >> > > > >> > > Regards > >> > > Kamal Kishore > >> > > >> > > >> > > >
