public function createDatabaseIndexes()
 {
     $collectionName = LexEntryModel::mapper($this->databaseName())->getCollectionName();
     $indexes = LexEntryModel::mapper($this->databaseName())->INDEXES_REQUIRED;
     MongoStore::addIndexesToCollection($this->databaseName(), $collectionName, $indexes);
     $collectionName = LexOptionListModel::mapper($this->databaseName())->getCollectionName();
     $indexes = LexOptionListModel::mapper($this->databaseName())->INDEXES_REQUIRED;
     MongoStore::addIndexesToCollection($this->databaseName(), $collectionName, $indexes);
 }