Remove invalid todos from database

db/migrate/20160309140734_fix_todos.rb

+class FixTodos < ActiveRecord::Migration
+ def up
+    execute <<-SQL
+      DELETE FROM todos
+      WHERE todos.target_type IN ('Commit', 'ProjectSnippet')
+         OR NOT EXISTS (
+              SELECT *
+              FROM projects
+              WHERE projects.id = todos.project_id
+            )
+    SQL
+ end
+
+ def down
+ end
+end

db/schema.rb

@@ -11,7 +11,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 20160305220806) do
+ActiveRecord::Schema.define(version: 20160309140734) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"