It all just depends on what you’re trying to do. Because I’m not entirely sure what you’re trying to do, here are a few patterns you may find useful.

Try to insert inside a transaction, if it fails, do something else, but let the transaction succeed

Repo.transaction(fn ->
  case Repo.insert(changeset) do
    {:ok, record} -> handle_success(record)
    _ -> do_something_else()
  end
end)

Try to insert something, if it succeeds insert something else, and rollback everything if there’s a failure:

Repo.transaction(fn ->
  with {:ok, record} <- Repo.insert(foo),
    {:ok, other_record} <- Repo.insert(bar) do
      {record, other_record}
  else
    val -> Repo.rollback(val)
  end
end)
|> case do
  {:ok, {foo, bar}} ->
    IO.puts "Both foo and bar were created because the transaction succeedd"
  {:error, error} ->
    IO.puts "Neither foo nor bar were created because the transaction failed with error: #{inspect error}"
end