gistfile1.txt

[debug] QUERY OK source="users" db=1.8ms decode=2.1ms queue=1.4ms idle=130.8ms
SELECT TRUE FROM "users" AS u0 WHERE (u0."email" = $1) LIMIT 1 ["kostas@live.com"]
#Ecto.Changeset<
  action: nil,
  changes: %{email: "kostas@live.com", password: "rubf6TFg"},
  errors: [],
  data: #Elijah.Accounts.User<>,
  valid?: true
>
#Ecto.Changeset<
  action: nil,
  changes: %{email: "netsfr@gmail.com", password: "P5uakr6F"},
  errors: [],
  data: #Elijah.Accounts.User<>,
  valid?: true
>
[debug] QUERY OK source="users" db=3.4ms idle=159.7ms
SELECT TRUE FROM "users" AS u0 WHERE (u0."email" = $1) LIMIT 1 ["netsfr@gmail.com"]
[debug] QUERY OK db=0.8ms idle=166.1ms
begin []
[debug] QUERY OK db=0.2ms
rollback []
** (Ecto.NoPrimaryKeyValueError) struct `#Elijah.Accounts.User<__meta__: #Ecto.Schema.Metadata<:built, "users">, avatar: nil, confirmed_at: nil, email: nil, hashed_password: nil, id: nil, inserted_at: nil, updated_at: nil, ...>` is missing primary key value
    (ecto 3.4.6) lib/ecto/repo/schema.ex:868: anonymous fn/3 in Ecto.Repo.Schema.add_pk_filter!/2
    (elixir 1.10.3) lib/enum.ex:2111: Enum."-reduce/3-lists^foldl/2-0-"/3
    (ecto 3.4.6) lib/ecto/repo/schema.ex:310: Ecto.Repo.Schema.do_update/4
    (ecto 3.4.6) lib/ecto/multi.ex:646: Ecto.Multi.apply_operation/5
    (elixir 1.10.3) lib/enum.ex:2111: Enum."-reduce/3-lists^foldl/2-0-"/3
    (ecto 3.4.6) lib/ecto/multi.ex:630: anonymous fn/5 in Ecto.Multi.apply_operations/5
    (ecto_sql 3.4.5) lib/ecto/adapters/sql.ex:875: anonymous fn/3 in Ecto.Adapters.SQL.checkout_or_transaction/4
    (db_connection 2.2.2) lib/db_connection.ex:1427: DBConnection.run_transaction/4
    (ecto 3.4.6) lib/ecto/repo/transaction.ex:20: Ecto.Repo.Transaction.transaction/4
    (elijah 0.1.0) lib/elijah/accounts.ex:119: Elijah.Accounts.register_users/1
    (elixir 1.10.3) lib/code.ex:926: Code.require_file/2
    (mix 1.10.3) lib/mix/tasks/run.ex:145: Mix.Tasks.Run.run/5
    (mix 1.10.3) lib/mix/tasks/run.ex:85: Mix.Tasks.Run.run/1
    (mix 1.10.3) lib/mix/task.ex:330: Mix.Task.run_task/3
    (mix 1.10.3) lib/mix/cli.ex:82: Mix.CLI.run_task/2

register_users.ex

  def register_users(attrs_list) do
      posts_multi =
        attrs_list
        |> Stream.map(fn user ->
          %User{}
          |> User.registration_changeset(user)
        end)
        |> Stream.map(fn user_cs ->
          IO.inspect(user_cs)
          # Create a Multi with a single update
          # operation, generating a unique key for the op.
          res = :crypto.hash(:sha256, user_cs.changes.email)
          |> Base.encode16()
          |> String.slice(-8..-2)

          key = String.to_atom("post_#{res}")
          Ecto.Multi.update(Ecto.Multi.new(), key, user_cs)
        end)
        |> Enum.reduce(Multi.new(), &Multi.append/2)

      posts_multi
      |> Repo.transaction()
      |> case do
        {:ok, %{user: user}} ->
          {:ok, user}

        {:error, _, error, _} ->
          {:error, error}
      end
  end

sql ddl:

-- DDL generated by Postico 1.5.12
-- Not all database features are supported. Do not use for backup.

-- Table Definition ----------------------------------------------

CREATE TABLE users (
    id BIGSERIAL PRIMARY KEY,
    email citext NOT NULL,
    hashed_password character varying(255) NOT NULL,
    confirmed_at timestamp(0) without time zone,
    inserted_at timestamp(0) without time zone NOT NULL,
    updated_at timestamp(0) without time zone NOT NULL,
    avatar character varying(255)
);

-- Indices -------------------------------------------------------

CREATE UNIQUE INDEX users_pkey ON users(id int8_ops);
CREATE UNIQUE INDEX users_email_index ON users(email citext_ops);