diff --git a/db/migrate/008_create_tasks.rb b/db/migrate/008_create_tasks.rb
--- a/db/migrate/008_create_tasks.rb
+++ b/db/migrate/008_create_tasks.rb
@@ -1,6 +1,6 @@
-class CreateTasks < ActiveRecord::Migration
+class CreateTasks < ActiveRecord::Migration[4.2]
   def self.up
-    create_table :tasks do |t|
+    create_table :tasks, options: "ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci" do |t|
       t.column 'submission_id', :integer
       t.column 'created_at', :datetime
     end