public Guid SaveTag(TagDTO tag) { Guid tagId = Guid.Empty; if (tag == null) throw new FaultException("Unable to save null tag."); TaskrDataContext db = new TaskrDataContext(ConfigurationProvider.GetConnection("Taskr")); if (tag.Id == Guid.Empty) { Tag _tag = tag.MapTo(); tagId = _tag.Id; db.Tags.InsertOnSubmit(_tag); } else { Tag _tag = db.Tags.SingleOrDefault(t => t.Id == tag.Id); tag.MapInto(_tag); tagId = _tag.Id; } db.SubmitChanges(); return tagId; }