: "Collections that do not specify numShards at collection creation time use : custom sharding and default to the "implicit" router. Document updates : received by a shard will be indexed to that shard, unless a "*shard*" : parameter or document field names a different shard."
the word "implicit" there may be somewhat confusin -- but yes otherwise that statement is correct (as i understand it). If you don't tell Solr in advance how many shards you want the collection to have, then it can't compute the shard assignments for you, and you are responsible for sending each doc to the appropriate shard. The other approach i was refering to is the way to explicitly override the document routing, even if you have a fixed number of shards -- there's a Java API you can use to do this (i don't recall what it is off the top of my head) but there is also a a mechanism using the default router code where having a "!" in your uniqueKey field will cause only the portion of the ID preceding the "!" to be used in computing the shard -- see the link i mentioned earlier. : I do specify the numShards parameter and that might be the confusion. The : admin UI is telling me that the routing is 'implicit' when it might not be? : Shouldn't it be compositeID routing if I use numShards? Again -- the terminology might be confusion .. i'm certainly confused, i'm not sure off the top of my head which one is refered to as "implicit". : > https://cwiki.apache.org/confluence/display/solr/Shards+and+Indexing+Data+in+SolrCloud : > https://cwiki.apache.org/confluence/display/solr/Distributed+Requests -Hoss
