danbooru/db/migrate/20170117233040_add_trigram_index_to_users.rb

class AddTrigramIndexToUsers < ActiveRecord::Migration[4.2]
  def change
    execute "set statement_timeout = 0"
    execute "create index index_users_on_name_trgm on users using gin (lower(name) gin_trgm_ops)"
  end
end