Something I forgot to mention - the collection shards can live on any number of machines, anywhere in the world. As long as the clusterstate in zk knows where the shard can be found (ie, a basis of SolrCloud) then everything will work. The example I gave had the shards living on the same machine but that is not a requirement.
On Fri, Dec 11, 2015 at 11:00 AM, Dennis Gove <dpg...@gmail.com> wrote: > Mugeesh, > > You can use Streaming Aggregation to provide various types of > cross-collection joins. This is currently available in trunk and will be a > part of Solr 6. > > To follow with your example, let's assume the following setup: > Restaurants: avail on machine1:8983 with 3 shards, zk at zk1:2345 > Users: avail on machine2:8983 with 2 shards, zk at zk2:2345 > Reviews: avail on machine1:8983 with 10 shards, zk at zk1:2345 > > You could send a streaming query to solr that would return all reviews for > restaurants in NYC and include the user's hometown > > hashJoin( > innerJoin( > search(users, q="*:*", fl="userId, full_name, hometown", sort="userId > asc", zkHost="zk2:2345", qt="/export"), > search(reviews, q="*:*", fl="userId, review, score", sort="userId > asc", zkHost="zk1:2345", qt="/export"), > on="userId" > ), > hashed=search(restaurants, q="city:nyc", fl="restaurantId, > restaurantName", sort="restaurantId asc", zkHost="zk1:2345", qt="/export"), > on="restaurantId" > ) > > Note that the # of shards doesn't matter and doesn't need to be considered > as a part of your query. Were you to send this off to a url for result, > it'd look like this > > http://machine1:8983/solr/users/stream?stream= > <http://localhost:8983/solr/careers/stream?stream=innerJoin(search(careers>[the > expression above] > > Additional information about Streaming API, Streaming Aggregation, and > Streaming Expressions can be found at > https://cwiki.apache.org/confluence/display/solr/Streaming+Expressions, > though this is currently incomplete as a lot of the new features have yet > to be added to the documentation. > > For those interested, joins were added under tickets > https://issues.apache.org/jira/browse/SOLR-7584 and > https://issues.apache.org/jira/browse/SOLR-8188. > > - Dennis > > > On Mon, Dec 7, 2015 at 7:42 AM, Mugeesh Husain <muge...@gmail.com> wrote: > >> I have create 3 cores on same machine using solrlcoud. >> core: Restaurant,User,Review >> each of core has only 1 shards and 2 replicas. >> >> Question >> 1.) It is possible to use join among 3 of cores on same machine( or >> different machine) >> 2.)I am struggling how to use join among 3 of core in solrlcoud mode. >> >> Client: is not interested to de-normalized data. >> >> Give some suggestion how to solved that problem. >> >> Thanks >> Mugeesh >> >> >> >> -- >> View this message in context: >> http://lucene.472066.n3.nabble.com/Joins-with-SolrCloud-tp4243957.html >> Sent from the Solr - User mailing list archive at Nabble.com. >> > >
