/// <summary>
/// Handler for the special case query that selects a specific instance of a type
/// </summary>
/// <typeparam name="T">The entity type to create for then instance if it is found</typeparam>
/// <param name="instanceIdentifier">The identifier for the instance</param>
/// <param name="typeIdentifier">The identifier for the type that the instance must be an instance of</param>
/// <returns>An enumerable that returns 0 or 1 instances of <typeparamref name="T"/>. If the resource identified
/// by <paramref name="instanceIdentifier"/> is an instance of the resource identifier by <paramref name="typeIdentifier"/>,
/// the enumeration returns a single object, otherwise it returns no objects.</returns>
public override IEnumerable <T> ExecuteInstanceQuery <T>(string instanceIdentifier, string typeIdentifier)
{
var sparqlQuery = String.Format("ASK {0} {{ <{1}> a <{2}>. }}", _store.GetDatasetClause(), instanceIdentifier, typeIdentifier);
var sparqResult = _store.ExecuteSparql(sparqlQuery);
var resultDoc = sparqResult.ResultDocument;
if (resultDoc.SparqlBooleanResult())
{
var dataObject = _store.MakeDataObject(instanceIdentifier);
yield return(BindDataObject <T>(dataObject, GetImplType(typeof(T))));
}
yield break;
}
