title: how to add group field in @Query annotation in Solr
body: <p>I have added a method to get quarters my repository class based on the value of book and year</p>
  
  <p><code>public interface Repository extends SolrCrudRepository&lt;Doc, Long&gt; {
      @Query(fields = { Constants.QUARTER_FIELD })
      public List&lt;CodingClinicDoc&gt; findQuarterByBookAndYear(String book, int year);
  }</code></p>
  
  <p>but i am getting duplicate values e.g. 'First quarter' around 10 times </p>
  
  <p>Please tell me if there is a way to apply group field like <code>group=true&amp;group.field=quarter</code> to <code>@Query</code> annotation to get unique result.
  Or some other way to get the distinct quarters.</p>