Fix Order By for alias

Author: bahusoid

src/NHibernate/Criterion/Order.cs

@@ -36,8 +36,7 @@ public Order(string propertyName, bool ascending)
 		/// </summary>
 		public virtual SqlString ToSqlString(ICriteria criteria, ICriteriaQuery criteriaQuery)
 		{
-			SqlString[] columns = CriterionUtil.GetColumnNames(propertyName, projection, criteriaQuery, criteria);
-			
+			SqlString[] columns = GetColumnsOrAliases(criteria, criteriaQuery);
 			bool[] toLowerColumns = ignoreCase ? FindStringColumns(criteria, criteriaQuery) : null;
 
 			var factory = criteriaQuery.Factory;
@@ -71,6 +70,14 @@ public virtual SqlString ToSqlString(ICriteria criteria, ICriteriaQuery criteria
 			return fragment.ToSqlString();
 		}
 
+		private SqlString[] GetColumnsOrAliases(ICriteria criteria, ICriteriaQuery criteriaQuery)
+		{
+			var propName = propertyName ?? (projection as IPropertyProjection)?.PropertyName;
+			return propName != null
+				? Array.ConvertAll(criteriaQuery.GetColumnAliasesUsingProjection(criteria, propName), x => new SqlString(x))
+				: CriterionUtil.GetColumnNamesUsingProjection(projection, criteriaQuery, criteria);
+		}
+
 		private bool[] FindStringColumns(ICriteria criteria, ICriteriaQuery criteriaQuery)
 		{
 			var type = projection == null