/// <summary>
/// Fills out a model of type <typeparamref name="T"/> using <c>traverse</c>. <paramref name="db"/> must be open.
/// </summary>
/// <remarks>
/// <para>Note that <c>traverse</c> can be slow, and <c>select</c> may be more appropriate. See
/// http://www.orientechnologies.com/docs/last/orientdb.wiki/SQL-Traverse.html#should-i-use-traverse-or-select
/// </para>
/// <para>Lightweight edges are not followed when populating model properties. Make sure to use "heavyweight" edges with either
/// <c>alter property MyEdgeClass.out MANDATORY=true</c> and <c>alter property MyEdgeClass.in MANDATORY=true</c>, or else
/// use <c>alter database custom useLightweightEdges=false</c>.</para>
/// </remarks>
/// <typeparam name="T">The model type. Must extend <see cref="ABaseModel"/>, have a parameterless constructor, and most importantly it must be in the same
/// namespace as <see cref="ABaseModel"/>.</typeparam>
/// <param name="db">The database to query</param>
/// <param name="from">The root RID to traverse.</param>
/// <returns>A model representing the record indicated by <paramref name="from"/>.</returns>
public static T Traverse <T>(this ODatabase db, ORID from) where T : ABaseModel, new()
{
// Traverse<T>(from.ToString()) is guaranteed to have 0 or 1 elements
return(db.Traverse <T>(from.ToString()).SingleOrDefault());
}