qb_akkoma/priv/repo/migrations/20190127151220_add_activities_likes_index.exs

defmodule Pleroma.Repo.Migrations.AddActivitiesLikesIndex do
  use Ecto.Migration
  @disable_ddl_transaction true

  def change do
    create index(:activities, ["((data #> '{\"object\",\"likes\"}'))"], concurrently: true, name: :activities_likes, using: :gin)
  end
end