Querying Related Entries¶

The OData Service allows traversing the associations defined in the views in order to get all the entities related with a particular entity. This is done by means of navigation properties:

/denodo-odata.svc/<database name>/collectionName(key)/navigationPropertyName

For example, being cities a navigation property in the entity type country that navigates towards the city entity type:

/denodo-odata.svc/movies/country(2)/cities

Response:

 {
   "@odata.context": "/denodo-odata.svc/movies/$metadata#city",
   "value": [
     {
       "city_id": 59,
       "city": "Batna",
       "country_id": 2,
       "last_update": "2006-02-15T11:45:25Z"
     },
     {
       "city_id": 63,
       "city": "Bchar",
       "country_id": 2,
       "last_update": "2006-02-15T11:45:25Z"
     },
     {
       "city_id": 483,
       "city": "Skikda",
       "country_id": 2,
       "last_update": "2006-02-15T11:45:25Z"
     }
   ]
 }

Referencing Related Entities¶

You can get the references to the collection of entities (instead of the actual entities) related with one particular entity.

To obtain this, add $ref to the URL (the old syntax /$links/ has been dropped in OData 4):

/denodo-odata.svc/<database name>/collectionName(key)/navProp/$ref

The URL specified below will show the references of every city associated with the entry country(2) through the navigation property cities:

/denodo-odata.svc/movies/country(2)/cities/$ref

Response:

{
  "@odata.context": "/denodo-odata.svc/movies/$metadata#cities",
  "value": [
    {
      "@odata.id": "city(59)"
    },
    {
      "@odata.id": "city(63)"
    },
    {
      "@odata.id": "city(483)"
    }
  ]
}