title: How to correctly boost results in Solr Dismax query
body: <p>I have managed to build an index in Solr which I can search on keyword, produce facets, query facets etc. This is all working great. I have implemented my search using a dismax query so it searches predetermined fields.</p>
  
  <p>However, my results are coming back sorted by score which appears to be calculated by keyword relevancy only. I would like to adjust the score where fields have pre-determined values. I think I can do this with boost query and boost functions but the documentation here:</p>
  
  <p><a href="http://wiki.apache.org/solr/DisMaxRequestHandler#head-6862070cf279d9a09bdab971309135c7aea22fb3" rel="nofollow noreferrer">http://wiki.apache.org/solr/DisMaxRequestHandler#head-6862070cf279d9a09bdab971309135c7aea22fb3</a></p>
  
  <p>Is not particularly helpful. I tried adding adding a bq argument to my search: </p>
  
  <pre><code>&amp;bq=media:DVD^2
  </code></pre>
  
  <p>(yes, this is an index of films!) but I find when I start adding more and more:</p>
  
  <pre><code>&amp;bq=media:DVD^2&amp;bq=media:BLU-RAY^1.5
  </code></pre>
  
  <p>I find the negative results - e.g. films that are DVD but are <strong>not</strong> BLU-RAY get negatively affected in their score. In the end it all seems to even out and my score is as it was before i started boosting.</p>
  
  <p>I must be doing this wrong and I wonder whether "boost function" comes in somewhere. Any ideas on how to correctly use boost?</p>