Why solr RemoveDuplicatesTokenFilterFactory dont work?

问题

My schema.xml is splitting product name and then uses RemoveDuplicate to remove duplicated words after split.

    <fieldType name="type_name" class="solr.TextField">
        <analyzer type="index">
            <tokenizer class="solr.PatternTokenizerFactory" pattern="\|| " />
            <filter class="solr.LowerCaseFilterFactory"/>
            <filter class="solr.RemoveDuplicatesTokenFilterFactory"/>

And in query analyzer I see that RemoveDuplicatesTokenFilterFactory did absolutely nothing to duplicated words. Why?

回答1:

If you read Wiki you will see that it only removes duplicates at the same position, which is not the case here.

来源：https://stackoverflow.com/questions/10329470/why-solr-removeduplicatestokenfilterfactory-dont-work