Reverse node reference

Question

I have 2 content types:

1. vehicles
2. engines

Several engine nodes are referenced to the single vehicle. Is there any way I can load all engines referenced to the single vehicle node if I have that vehicle node object (thus the nid as well)?

I use Node reference module.

If you need any more info, please ask. Thanks in advance!

Answer 1

I found a solution to this issue by performing a query on 'field_data_field_vehicle_reference' table.

For my case, the solution can be something like this:

function engines_of_vehicle($vehicle) {
  $nid = $vehicle->nid;

  // get all engine nids referenced to this vehicle
  $engine_nids = db_query('SELECT ref.entity_id FROM {field_data_field_vehicle_reference} ref WHERE ref.field_vehicle_reference_nid  =:nid AND ref.bundle =:bundle', array(':nid' => $nid, ':bundle' => 'engine'))->fetchCol();

  //load all engines referenced to this nid
  $engines = node_load_multiple($engine_nids);

  return $engines;    
}