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.

db/migrate/20220611192407_create_subprincipleitemgroups.rb

@@ -0,0 +1,10 @@
+class CreateSubprincipleitemgroups < ActiveRecord::Migration[7.0]
+  def change
+    create_table :subprincipleitemgroups do |t|
+      t.references :subprinciple, null: false, foreign_key: true
+      t.string :type
+
+      t.timestamps
+    end
+  end
+end