+
+removing an obsolete commodity:
+
+ select * from (select * from sell union select * from buy) left outer join commods using (commodid) where commods.commodname = 'Black dye' limit 10;
+
+if that produces no output then:
+
+ begin;
+ delete from commods where commodname like 'Black dye';
+ select * from (select * from sell union select * from buy) left outer join commods using (commodid) where commods.commodname is null limit 10;
+
+and if that produces no output then:
+ commit;
+otherwise
+ rollback;
+
+=======================================
+
+ceb's example route:
+ alpha,byrne,papaya,turtle,jorvik,luthien
+
+example mixed arbitrage/trade
+ xi,heph
+
+========================================
+
To remedy bug fixed in 01c14767c024ac56686dbbfcd88d9f3a0b4b1574,
did this: