Developer Tip: Maintain broken relationship in taxonomy migration

$relation_ship_info = array('source_table' => 'ismaili_tag', // Name of source table for migration
      'map_table' => 'migrate_map_geographyterm', // migrate generated table
      'parent_field_name' => 'parenttagid', // name of parent field in source table
      'source_map_field' => 'tagid' // name of field used in migration
);

MYMODULE_handle_broken_relationship($relation_ship_info);
/**
 * Process Content Category Term names
 * @param  [type] $relation_ship_info     Holds all information for maintaing broken parent-child
 * relationship. 
 * @return [type] [description]
 */
function MYMODULE_handle_broken_relationship($relation_ship_info) {
  $query = "SELECT mc.sourceid1, mc.destid1, cs." . $relation_ship_info['parent_field_name'] ." FROM " . $relation_ship_info['source_table'] ." cs
    left join " . $relation_ship_info['map_table'] ." mc ON (cs." . $relation_ship_info['source_map_field'] ." = mc.sourceid1)
    left join taxonomy_term_hierarchy th ON (mc.destid1 = th.tid)
    WHERE th.parent = 0 and cs." . $relation_ship_info['parent_field_name'] . " > 0";
  $result = db_query($query);
  $missing_tid_parentid = '';
  foreach($result as $data) {
    $missing_content_data[$data->sourceid1] = $data;
    $missing_tid_parentid = ($missing_tid_parentid != '') ? $missing_tid_parentid . "," .$data->{$relation_ship_info['parent_field_name']} : $data->{$relation_ship_info['parent_field_name']};
  }
  if ($missing_tid_parentid != '') {
    $parent_data = MYMODULE_fetch_category_info($missing_tid_parentid, $relation_ship_info);
    MYMODULE_complete_term_relationship($missing_content_data, $parent_data, $relation_ship_info);
  }
}

 /**
 * Fetch parent terms for missing terms
 * @param  [type] $missing_tid_parentid
 * @param  [type] $relation_ship_info
 * @return [type] [description]
 */
function MYMODULE_fetch_category_info($missing_tid_parentid, $relation_ship_info) {
  $parent_data = array();
  $query = "SELECT sourceid1, destid1 FROM " . $relation_ship_info['map_table'] . "
    WHERE sourceid1 in (" . $missing_tid_parentid. ")";
  $result = db_query($query);
  foreach($result as $data) {
    $parent_data[$data->sourceid1] = $data;
  }
  return $parent_data;
}

/**
 * Update taxonomy_term_hierarchy for missing parents
 * @param  [type] $missing_content_data [description]
 * @param  [type] $parent_data          [description]
 * @param  [type] $parent_data          [description]
 * @param  [type] $relation_ship_info   [description]
 * @return [type]                       [description]
 */
function MYMODULE_complete_term_relationship($missing_content_data, $parent_data, $relation_ship_info) {
  $total = 0;
  $output = "";
  foreach ($missing_content_data as $key => $data) {
    $missing_tid = $data->destid1;
    $ptid = $data->{$relation_ship_info['parent_field_name']};
    $missing_parent_tid = $parent_data[$ptid]->destid1;
    if (!$missing_parent_tid) {
      continue;
    }
    $total++;
    db_update("taxonomy_term_hierarchy")      ->condition('tid', $missing_tid)
      ->fields(array('parent' => $missing_parent_tid))
      ->execute();
    $output .=  "
 Map $missing_tid -> $missing_parent_tid";
  }
  echo "
Repaired total ::", $total, " terms";
  print $output;
}