Apache Solr automatically search with (*)

Question

Good evening,

when I search for the word "app" it dont show the word "apple". But if I search for "app*", it show "apple" and "app". I dont want to write "*" in the search bar. How can I do this if I only search for "app" and it shows "apple" and "app"?

  <fieldType name="text_general" class="solr.TextField" positionIncrementGap="100" multiValued="true">
<analyzer type="index">
  <tokenizer class="solr.StandardTokenizerFactory"/>
  <filter class="solr.StopFilterFactory" words="stopwords.txt" ignoreCase="true"/>
  <filter class="solr.LowerCaseFilterFactory"/>
</analyzer>
<analyzer type="query">
  <tokenizer class="solr.StandardTokenizerFactory"/>
  <filter class="solr.StopFilterFactory" words="stopwords.txt" ignoreCase="true"/>
  <filter class="solr.SynonymFilterFactory" expand="true" ignoreCase="true" synonyms="synonyms.txt"/>
  <filter class="solr.LowerCaseFilterFactory"/>
</analyzer>

I tried to add <filter class="solr.ReversedWildcardFilterFactory"/> but it didnt work.

Can someone help me?

I use Apache Solr 6.4.1

Sry for my bad english.

Answer 1

Use EdgeNGramFilterFactory

EdgeNGramFilterFactory :

This filter generates edge n-gram tokens of sizes within the given range.

Arguments:

• minGramSize: (integer, default 1) The minimum gram size.
• maxGramSize: (integer, default 1) The maximum gram size.

Example :

If we use minGramSize = 1 and maxGramSize = 4 then

In: "four score"
Tokenizer to Filter: "four", "score"
Out: "f", "fo", "fou", "four", "s", "sc", "sco", "scor"

For your case you can use the below schema :

<fieldType name="text_ngram" class="solr.TextField" positionIncrementGap="100">
    <analyzer type="index">
      <tokenizer class="solr.StandardTokenizerFactory"/>
      <filter class="solr.StopFilterFactory" words="stopwords.txt" ignoreCase="true"/>
      <filter class="solr.LowerCaseFilterFactory" />
      <filter class="solr.EdgeNGramFilterFactory" minGramSize="1" maxGramSize="200"/>
     </analyzer>
    <analyzer type="query">
      <tokenizer class="solr.StandardTokenizerFactory"/>
      <filter class="solr.StopFilterFactory" words="stopwords.txt" ignoreCase="true"/>
      <filter class="solr.SynonymFilterFactory" expand="true" ignoreCase="true" synonyms="synonyms.txt"/>
      <filter class="solr.LowerCaseFilterFactory" />
    </analyzer>
</fieldType>

And update your fieldType to text_ngram Ex.

<field name="name" type="text_ngram" indexed="true" stored="false" multiValued="true"/>

Note : Don't forget to reload the core and reindex data