It is PRINCIPLES - truths; not PRINCIPALS - people in charge of schools or racing teams.

By deleteing the dev database, recreating it from migrations and then preparing the test database; the foreign key contraints now work. Also the database tables are now uft8mb4 instead of lantin1.

May be an idea to do this every time there is a rails update until going live.

test/fixtures/subprincipleitemgroups.yml

@@ -0,0 +1,9 @@
+# Read about fixtures at https://api.rubyonrails.org/classes/ActiveRecord/FixtureSet.html
+
+# one:
+#   subprinciple: one
+#   type:
+#
+# two:
+#   subprinciple: two
+#   type: