title: MongoDb corrupt collection?
body: <p>I have a sharded Mongo 2.4.3 setup</p>
  
  <p>When I want to try to run a query on one of my collections, i get the error <code>exception: BSONObj size: 0 (0x00000000) is invalid. Size must be between 0 and 16793600(16MB) First element: EOO</code></p>
  
  <p>I've already ran a <code>db.repairDatabase</code>, but that didn't seem to have helped much.</p>
  
  <p>When I just do <code>db.collection.findOne()</code>, it runs fine, but when i do e.g. <code>db.collection.find({'_id': {'$gte': ObjectId("52631d000000000000000000")}}</code>, i get the error above.</p>
  
  <p>I've read that this might is because of a corrupt index, so I tried:</p>
  
  <pre><code>db.collection.reIndex();
  {
      "raw" : {
          "rs0/ec2-xx-xxx-xxx-xxx.us-west-2.compute.amazonaws.com:27017,ec2-xx-xxx-xxx-xxx.us-west-2.compute.amazonaws.com:27017,ec2-xx-xx-xxx-xx.us-west-2.compute.amazonaws.com:27017" : {
              "nIndexesWas" : 2,
              "errmsg" : "exception: BSONObj size: 0 (0x00000000) is invalid. Size must be between 0 and 16793600(16MB) First element: EOO",
              "code" : 10334,
              "ok" : 0
          }
      },
      "ok" : 0,
      "errmsg" : "{ rs0/ec2-xx-xxx-xxx-xxx.us-west-2.compute.amazonaws.com:27017,ec2-xx-xxx-xxx-xxx.us-west-2.compute.amazonaws.com:27017,ec2-xx-xxx-xxx-xx.us-west-2.compute.amazonaws.com:27017: \"exception: BSONObj size: 0 (0x00000000) is invalid. Size must be between 0 and 16793600(16MB) First element: EOO\" }"
  }
  </code></pre>
  
  <p>I've also dropped all indexes before doing this, only the one on _id is left</p>
  
  <pre><code>db.collection.getIndexes();
  [
      {
          "v" : 1,
          "key" : {
              "_id" : 1
          },
          "ns" : "db.collection",
          "name" : "_id_"
      }
  ]
  </code></pre>
  
  <p>Still no luck and I'm running out of ideas here. Anyone has another suggestion? The collection has about 900M documents, so I realy need to recover this</p>