add index on blob checksum

db/migrate/20240228083356_add_index_on_blobs_checksum.rb

@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+class AddIndexOnBlobsChecksum < ActiveRecord::Migration[7.1]
+  def change
+    add_index :active_storage_blobs, :checksum
+  end
+end