--- a/lib/thingfish/metastore/pggraph/node.rb	Tue Nov 01 17:12:49 2016 -0700
+++ b/lib/thingfish/metastore/pggraph/node.rb	Wed Nov 09 22:38:18 2016 -0800
@@ -54,9 +54,11 @@
 				#
 				else
 					if field.to_sym == :relationship
-						ds = self.join_edges.filter( Sequel.pg_jsonb( :edges__prop ).get_text( field.to_s ) => value )
+						ds = ds.join_edges unless ds.joined_dataset?
+						ds = ds.filter( Sequel.pg_jsonb( :edges__prop ).get_text( field.to_s ) => value )
 
 					elsif field.to_sym == :relation
+						ds = ds.join_edges unless ds.joined_dataset?
 						ds = self.join_edges.filter( :edges__id_p => value )
 
 					else