Snippet of my Solr config

schema.xml

<schema name="Trigram" version="1.4">
<!-- this is heavily truncated, but I hope it has the relevant stuff in -->
<types>
  <fieldType name="title_trigram" class="solr.TextField"
             positionIncrementGap="100" stored="false" multiValued="true">
    <analyzer type="index">
      <tokenizer class="solr.KeywordTokenizerFactory"/>
      <filter class="solr.LowerCaseFilterFactory"/>
      <filter class="solr.NGramFilterFactory" minGramSize="3"
            maxGramSize="3"/>
    </analyzer>
    <analyzer type="query">
      <tokenizer class="solr.KeywordTokenizerFactory"/>
      <filter class="solr.LowerCaseFilterFactory"/>
      <filter class="solr.NGramFilterFactory" minGramSize="3"
            maxGramSize="3"/>
    </analyzer>
  </fieldType>
</types>

<fields>
    <field name="id" type="string" indexed="true" stored="true" required="true" />
    <field name="title" type="string" indexed="true" stored="true" required="true" />
    <field name="title_trigram" type="trigram" indexed="true" stored="true" required="true" />
</fields>

<uniqueKey>id</uniqueKey>

<defaultSearchField>title_trigram</defaultSearchField>

<!-- SolrQueryParser configuration: defaultOperator="AND|OR" -->
<solrQueryParser defaultOperator="OR"/>

<copyField source="title" dest="title_trigram"/>

</schema>