begin transaction isolation level serializable;
do $$
  declare migration integer;
begin
  migration := 14;

  if (SELECT myproject.perform_migration(migration, 'Add "middle name" column')) then
    RAISE NOTICE 'Performing migration %', migration;

    ALTER TABLE myproject.users ADD COLUMN middle_name TEXT NULL;

  else
    raise notice 'Not performing migration %', migration;
  end if;
end$$;
commit;