title: do not index all fields using plucene::simple
body: <p>i am looking at plucene for storing a large amount of data and i am very new at this. Each record of the data has a unique ID and 3 more fields. The fields have lots of text but i want just the id to be searchable/indexed so when i provide an id i can retrieve the other fields. A simple example piece of code is this:</p>
  
  <pre><code>my $newIndex = Plucene::Simple-&gt;open("data");
  $newIndex-&gt;add(id1 =&gt; {pubmedID =&gt; "1223323", title =&gt; "a_title", abstract =&gt; "an abstract"}); 
  my @results = $newIndex-&gt;search("1223323");
  </code></pre>
  
  <p>I am trying to use plucene::simple and I have 2 questions/problems:</p>
  
  <ol>
  <li>i cannot see an option for not indexing some of the fields. </li>
  <li>in the <code>@results</code> array I will get <code>'id1'</code>. How can I get back e.g. the abstract field?</li>
  </ol>
  
  <p>Thanks in advance</p>