Import fails due to duplicate entries

Hi,
Found needed to clean the data before migrate as there were some duplicate path entries, added a hook_install to clean out duplicate enties and leave the most recent ones:

function xxxx_update_7025() {
  // remove dupicate entries
  $query = db_select('files', 'f');
  $query->addField('f', 'filepath', 'filepath');
  $query->addField('f', 'fid', 'fid');
  $query->addExpression('COUNT(*)', 'count');
  $query->groupBy('filepath');
  $query->orderBy('fid', 'ASC'); 
  $results = $query->execute();
  foreach ($results as $result) {
    if($result->count>1){
      db_delete('files')->condition(fid, $result->fid, '!=')->execute(); 
    }
  }
}