I'm trying a modified schema.xml with solr - it appears I now have substring searches!

I took the schema.xml file shipped with Dovecot, and modified the text field definition to be:

<fieldType name="text" class="solr.TextField" positionIncrementGap="100"> <analyzer type="index"> <tokenizer class="solr.WhitespaceTokenizerFactory"/> <filter class="solr.StopFilterFactory" ignoreCase="true" words="stopwords.txt"/> <filter class="solr.WordDelimiterFilterFactory" generateWordParts="1" generateNumberParts="1" catenateWords="1" catenateNumbers="1" catenateAll="0"/> <filter class="solr.LowerCaseFilterFactory"/> <filter class="solr.SnowballPorterFilterFactory" protected="protwords.txt"/> <filter class="solr.NGramFilterFactory" minGramSize="3" maxGramSize="15"/> <filter class="solr.RemoveDuplicatesTokenFilterFactory"/> </analyzer> <analyzer type="query"> <tokenizer class="solr.WhitespaceTokenizerFactory"/> <filter class="solr.SynonymFilterFactory" synonyms="synonyms.txt" ignoreCase="true" expand="true"/> <filter class="solr.StopFilterFactory" ignoreCase="true" words="stopwords.txt"/> <filter class="solr.WordDelimiterFilterFactory" generateWordParts="1" generateNumberParts="1" catenateWords="0" catenateNumbers="0" catenateAll="0"/> <filter class="solr.LowerCaseFilterFactory"/> <filter class="solr.SnowballPorterFilterFactory" protected="protwords.txt"/> <filter class="solr.RemoveDuplicatesTokenFilterFactory"/> </analyzer> </fieldType>

Changing to the new "SnowballPorter" instead of the deprecated "EnglishPorter" filters is probably minor - the magic is the "NGramFilterFactory". 3 & 15 seemed reasonable defaults for the min/max size to search on.

Daniel