(cannot_coerce) cannot cast type jsonb to jsonb[] when updating list of embeds field with jsonb as underlying type #614
Description
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Versions
1.18.4 OTP 27
27.3.3
Operating system
macos
Current Behavior
Following up discussion on Elixir Discord. jsonb (or map) is the recommended type for storing list of embeds in Ecto. Naturally, I tried to do the same with Ash, but run into an error during update.
Reproduction
Here's a one file reproduction
Mix.install(
[
{:ash, "~> 3.0"},
{:ash_postgres, "~> 2.0"}
],
consolidate_protocols: false
)
Application.put_env(:myapp, MyRepo,
database: "mix_install_examples",
username: "postgres",
password: "postgres",
hostname: "localhost"
)
defmodule MyRepo do
use AshPostgres.Repo, otp_app: :myapp
end
defmodule Migration0 do
use Ecto.Migration
def change do
create table("profiles") do
add(:name, :string)
add(:identities, :jsonb)
add :inserted_at, :utc_datetime_usec,
null: false,
default: fragment("(now() AT TIME ZONE 'utc')")
add :updated_at, :utc_datetime_usec,
null: false,
default: fragment("(now() AT TIME ZONE 'utc')")
end
end
end
defmodule Accounts.Profile.Identity do
use Ash.TypedStruct
typed_struct do
field :first_name, :string, allow_nil?: false
field :last_name, :string
end
end
defmodule Accounts.Profile do
use Ash.Resource,
domain: Accounts,
data_layer: AshPostgres.DataLayer
postgres do
table "profiles"
repo MyRepo
end
actions do
defaults [:read, :destroy, create: [:name, :identities], update: [:name, :identities]]
end
attributes do
integer_primary_key :id
attribute :name, :string
attribute :identities, {:array, Accounts.Profile.Identity}, default: []
timestamps()
end
end
defmodule Accounts do
use Ash.Domain, validate_config_inclusion?: false
resources do
resource Accounts.Profile do
define :all_profiles, action: :read
define :profile_by_id, action: :read, get_by: [:id]
define :create_profile, args: [:name], action: :create
define :update_profile, action: :update
define :delete_profile, action: :destroy
end
end
end
defmodule Main do
import Ecto.Query, warn: false
def main do
MyRepo.__adapter__().storage_down(MyRepo.config())
:ok = MyRepo.__adapter__().storage_up(MyRepo.config())
{:ok, _} = MyRepo.start_link([])
Ecto.Migrator.run(MyRepo, [{0, Migration0}], :up, all: true, log_migrations_sql: :info)
profile =
Accounts.Profile
|> Ash.Changeset.for_create(:create, %{name: "Joe Armstrong"})
|> Ash.create!()
profile.id
|> Accounts.update_profile!(%{identities: [%{first_name: "Foo", last_name: "Bar"}]})
|> IO.inspect()
end
end
Main.main()error
elixir ash_postgres.exs
17:11:16.391 [info] == Running 0 Migration0.change/0 forward
17:11:16.393 [info] create table profiles
17:11:16.395 [info] QUERY OK db=2.0ms
CREATE TABLE "profiles" ("id" bigserial, "name" varchar(255), "identities" jsonb, "inserted_at" timestamp DEFAULT (now() AT TIME ZONE 'utc') NOT NULL, "updated_at" timestamp DEFAULT (now() AT TIME ZONE 'utc') NOT NULL, PRIMARY KEY ("id")) []
17:11:16.396 [info] == Migrated 0 in 0.0s
17:11:16.429 [debug] QUERY OK db=0.6ms idle=57.8ms
begin []
17:11:16.442 [debug] QUERY OK source="profiles" db=5.9ms
INSERT INTO "profiles" ("name","identities","inserted_at","updated_at") VALUES ($1,$2,$3,$4) RETURNING "updated_at","inserted_at","identities","name","id" ["Joe Armstrong", [], ~U[2025-09-09 00:11:16.426384Z], ~U[2025-09-09 00:11:16.426384Z]]
17:11:16.445 [debug] QUERY OK db=0.8ms
commit []
17:11:16.501 [debug] QUERY ERROR source="profiles" db=0.0ms queue=3.0ms idle=127.1ms
UPDATE "profiles" AS p0 SET "updated_at" = s1."__new_updated_at", "identities" = s1."__new_identities" FROM (SELECT sp0."id" AS "id", (CASE WHEN $1::jsonb[] != sp0."identities"::jsonb[] THEN $2::timestamp ELSE sp0."updated_at"::timestamp END)::timestamp AS "__new_updated_at", $3::jsonb[] AS "__new_identities" FROM "profiles" AS sp0 WHERE (sp0."id"::bigint = $4::bigint) LIMIT $5) AS s1 WHERE (p0."id" = s1."id") RETURNING p0."id", p0."name", p0."identities", p0."inserted_at", p0."updated_at" [[%Accounts.Profile.Identity{first_name: "Foo", last_name: "Bar"}], ~U[2025-09-09 00:11:16.495357Z], [%Accounts.Profile.Identity{first_name: "Foo", last_name: "Bar"}], 1, 1]
** (Ash.Error.Unknown)
Bread Crumbs:
> Returned from bulk query update: Accounts.Profile.update
Unknown Error
* ** (Postgrex.Error) ERROR 42846 (cannot_coerce) cannot cast type jsonb to jsonb[]
query: UPDATE "profiles" AS p0 SET "updated_at" = s1."__new_updated_at", "identities" = s1."__new_identities" FROM (SELECT sp0."id" AS "id", (CASE WHEN $1::jsonb[] != sp0."identities"::jsonb[] THEN $2::timestamp ELSE sp0."updated_at"::timestamp END)::timestamp AS "__new_updated_at", $3::jsonb[] AS "__new_identities" FROM "profiles" AS sp0 WHERE (sp0."id"::bigint = $4::bigint) LIMIT $5) AS s1 WHERE (p0."id" = s1."id") RETURNING p0."id", p0."name", p0."identities", p0."inserted_at", p0."updated_at"
(ecto_sql 3.13.2) lib/ecto/adapters/sql.ex:1098: Ecto.Adapters.SQL.raise_sql_call_error/1
(ecto_sql 3.13.2) lib/ecto/adapters/sql.ex:996: Ecto.Adapters.SQL.execute/6
(ecto 3.13.2) lib/ecto/repo/queryable.ex:241: Ecto.Repo.Queryable.execute/4
(ash_postgres 2.6.17) lib/data_layer.ex:1577: AshPostgres.DataLayer.update_query/4
(ash 3.5.39) lib/ash/actions/update/bulk.ex:608: Ash.Actions.Update.Bulk.do_atomic_update/5
(ash 3.5.39) lib/ash/actions/update/bulk.ex:293: Ash.Actions.Update.Bulk.run/6
(ash 3.5.39) lib/ash.ex:3320: Ash.bulk_update!/4
/Users/amartsinovich/Library/Caches/mix/installs/elixir-1.18.4-erts-15.2.6/617f01c5d311df92f70ed4380fa03884/deps/ash/lib/ash/code_interface.ex:1215: Accounts.update_profile!/3
(ash 3.5.39) lib/ash.ex:3340: Ash.bulk_update!/4
/Users/amartsinovich/Library/Caches/mix/installs/elixir-1.18.4-erts-15.2.6/617f01c5d311df92f70ed4380fa03884/deps/ash/lib/ash/code_interface.ex:1215: Accounts.update_profile!/3
ash_postgres.exs:99: Main.main/0
ash_postgres.exs:104: (file)
Expected Behavior
No response