title: Using more than one geospatial index per collection in MongoDB
body: <p><a href="http://www.mongodb.org/display/DOCS/Geospatial+Indexing/#GeospatialIndexing-CreatingtheIndex" rel="nofollow">Current MongoDB</a> documentation states the following:</p>
  
  <blockquote>
    <p><strong>You may only have 1 geospatial index per collection, for now.</strong> While
    MongoDB may allow to create multiple indexes, this behavior is
    unsupported. Because MongoDB can only use one index to support a
    single query, in most cases, having multiple geo indexes will produce
    undesirable behavior.</p>
  </blockquote>
  
  <p>However, when I create two geospatial indices in a collection (using Mongoose), they work just fine:</p>
  
  <pre><code>MySchema.index({
    'loc1': '2d',
    extraField1: 1,
    extraField2: 1
  });
  
  MySchema.index({
    'loc2': '2d',
    extraField1: 1,
    extraField2: 1
  });
  </code></pre>
  
  <p>My question is this: while it seems to work, the MongoDB documentation says this could "produce undesirable behavior". So far, nothing undesirable has not yet been discovered neither in testing or use.</p>
  
  <p><strong>Should I be concerned about this? If the answer is yes then what would you recommend as a workaround?</strong></p>