solr - execute multiple queries in one request

Question

Is there a way to execute multiple queries in a single solr request and get the union of results as response

my simplified schema would look like a name field and a type field(4-5 different types) and I want 10 results per type value. can this be done in solr?

Answer 1

Currently not possible, Look at this request, possibly when this fix is in place

https://issues.apache.org/jira/browse/SOLR-1093

Answer 2

I think this can be done w/ Field Collapsing

http://wiki.apache.org/solr/FieldCollapsing#Quick_Start

Their example is similar except instead of types they are splitting the price into ranges:

We can find the top documents that also match arbitrary queries with the group.query command (much like facet.query). For example, we could use this to find the top 3 documents with in different price ranges:

http://localhost:8983/solr/select?wt=json&indent=true&fl=name,price&q=memory&group=true&group.query=price:[0+TO+99.99]&group.query=price:[100+TO+*]&group.limit=3

In your case group.limit=10.

Answer 3

This can be accomplished by field grouping or field collapsing.

For example: (separate lines for readability)

http://mysolrhost/select?
&q=*
&fl=name,type
&count=50
&group=true
&group.field=type
&group.limit=10
&group.main=true

References:

• https://solr.apache.org/guide/6_6/result-grouping.html
• https://cwiki.apache.org/confluence/display/solr/FieldCollapsing#Quick_Start

Related question with additional details:

• Is it possible to return 10 SOLR docs that match one condition and 10 docs that match another condition for a total of count=20 docs in same query?

Answer 4

Federated Search

Distributed Search - needs all the definition schemas to look the same