diff --git a/priv/resource_snapshots/test_repo/points/20250313112823.json b/priv/resource_snapshots/test_repo/points/20250313112823.json
new file mode 100644
index 00000000..83a5bc87
--- /dev/null
+++ b/priv/resource_snapshots/test_repo/points/20250313112823.json
@@ -0,0 +1,47 @@
+{
+  "attributes": [
+    {
+      "allow_nil?": false,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": true,
+      "references": null,
+      "size": null,
+      "source": "id",
+      "type": [
+        "array",
+        "float"
+      ]
+    }
+  ],
+  "base_filter": null,
+  "check_constraints": [],
+  "custom_indexes": [],
+  "custom_statements": [],
+  "has_create_action": true,
+  "hash": "1E2378D30CF657B673E7EE140FDD4CA067E23FB8862A8F05D35A3F680EBA06B4",
+  "identities": [
+    {
+      "all_tenants?": false,
+      "base_filter": null,
+      "index_name": "points_id_index",
+      "keys": [
+        {
+          "type": "atom",
+          "value": "id"
+        }
+      ],
+      "name": "id",
+      "nils_distinct?": true,
+      "where": null
+    }
+  ],
+  "multitenancy": {
+    "attribute": null,
+    "global": null,
+    "strategy": null
+  },
+  "repo": "Elixir.AshPostgres.TestRepo",
+  "schema": null,
+  "table": "points"
+}
\ No newline at end of file
diff --git a/priv/resource_snapshots/test_repo/posts/20250313112823.json b/priv/resource_snapshots/test_repo/posts/20250313112823.json
new file mode 100644
index 00000000..cd1bb56d
--- /dev/null
+++ b/priv/resource_snapshots/test_repo/posts/20250313112823.json
@@ -0,0 +1,580 @@
+{
+  "attributes": [
+    {
+      "allow_nil?": false,
+      "default": "fragment(\"gen_random_uuid()\")",
+      "generated?": false,
+      "primary_key?": true,
+      "references": null,
+      "size": null,
+      "source": "id",
+      "type": "uuid"
+    },
+    {
+      "allow_nil?": false,
+      "default": "1",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "version",
+      "type": "bigint"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "title_column",
+      "type": "text"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "not_selected_by_default",
+      "type": "text"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "datetime",
+      "type": "timestamptz(6)"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "score",
+      "type": "bigint"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "limited_score",
+      "type": "bigint"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "public",
+      "type": "boolean"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "category",
+      "type": "citext"
+    },
+    {
+      "allow_nil?": true,
+      "default": "\"sponsored\"",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "type",
+      "type": "text"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "price",
+      "type": "bigint"
+    },
+    {
+      "allow_nil?": true,
+      "default": "\"0\"",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "decimal",
+      "type": "decimal"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "status",
+      "type": "text"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "status_enum",
+      "type": "status"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "metadata",
+      "type": "map"
+    },
+    {
+      "allow_nil?": false,
+      "default": "2",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "constrained_int",
+      "type": "bigint"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "point",
+      "type": [
+        "array",
+        "float"
+      ]
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "composite_point",
+      "type": "custom_point"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "string_point",
+      "type": "text"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "stuff",
+      "type": "map"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "list_of_stuff",
+      "type": [
+        "array",
+        "map"
+      ]
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "uniq_one",
+      "type": "text"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "uniq_two",
+      "type": "text"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "uniq_custom_one",
+      "type": "text"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "uniq_custom_two",
+      "type": "text"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "uniq_on_upper",
+      "type": "text"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "uniq_if_contains_foo",
+      "type": "text"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "list_containing_nils",
+      "type": [
+        "array",
+        "text"
+      ]
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "ltree_unescaped",
+      "type": "ltree"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "ltree_escaped",
+      "type": "ltree"
+    },
+    {
+      "allow_nil?": false,
+      "default": "fragment(\"(now() AT TIME ZONE 'utc')\")",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "created_at",
+      "type": "utc_datetime_usec"
+    },
+    {
+      "allow_nil?": false,
+      "default": "fragment(\"(now() AT TIME ZONE 'utc')\")",
+      "generated?": false,
+      "primary_key?": false,
+      "references": null,
+      "size": null,
+      "source": "updated_at",
+      "type": "timestamptz(6)"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": {
+        "deferrable": false,
+        "destination_attribute": "id",
+        "destination_attribute_default": null,
+        "destination_attribute_generated": null,
+        "index?": false,
+        "match_type": null,
+        "match_with": null,
+        "multitenancy": {
+          "attribute": null,
+          "global": null,
+          "strategy": null
+        },
+        "name": "posts_organization_id_fkey",
+        "on_delete": null,
+        "on_update": null,
+        "primary_key?": true,
+        "schema": "public",
+        "table": "orgs"
+      },
+      "size": null,
+      "source": "organization_id",
+      "type": "uuid"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": {
+        "deferrable": false,
+        "destination_attribute": "id",
+        "destination_attribute_default": null,
+        "destination_attribute_generated": null,
+        "index?": false,
+        "match_type": null,
+        "match_with": null,
+        "multitenancy": {
+          "attribute": null,
+          "global": null,
+          "strategy": null
+        },
+        "name": "posts_parent_post_id_fkey",
+        "on_delete": null,
+        "on_update": null,
+        "primary_key?": true,
+        "schema": "public",
+        "table": "posts"
+      },
+      "size": null,
+      "source": "parent_post_id",
+      "type": "uuid"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": {
+        "deferrable": false,
+        "destination_attribute": "id",
+        "destination_attribute_default": null,
+        "destination_attribute_generated": null,
+        "index?": false,
+        "match_type": null,
+        "match_with": null,
+        "multitenancy": {
+          "attribute": null,
+          "global": null,
+          "strategy": null
+        },
+        "name": "posts_author_id_fkey",
+        "on_delete": null,
+        "on_update": null,
+        "primary_key?": true,
+        "schema": "public",
+        "table": "authors"
+      },
+      "size": null,
+      "source": "author_id",
+      "type": "uuid"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": {
+        "deferrable": false,
+        "destination_attribute": "id",
+        "destination_attribute_default": null,
+        "destination_attribute_generated": null,
+        "index?": false,
+        "match_type": null,
+        "match_with": null,
+        "multitenancy": {
+          "attribute": null,
+          "global": null,
+          "strategy": null
+        },
+        "name": "posts_db_point_id_fkey",
+        "on_delete": null,
+        "on_update": null,
+        "primary_key?": true,
+        "schema": "public",
+        "table": "points"
+      },
+      "size": null,
+      "source": "db_point_id",
+      "type": [
+        "array",
+        "float"
+      ]
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": false,
+      "references": {
+        "deferrable": false,
+        "destination_attribute": "id",
+        "destination_attribute_default": null,
+        "destination_attribute_generated": null,
+        "index?": false,
+        "match_type": null,
+        "match_with": null,
+        "multitenancy": {
+          "attribute": null,
+          "global": null,
+          "strategy": null
+        },
+        "name": "posts_db_string_point_id_fkey",
+        "on_delete": null,
+        "on_update": null,
+        "primary_key?": true,
+        "schema": "public",
+        "table": "string_points"
+      },
+      "size": null,
+      "source": "db_string_point_id",
+      "type": "text"
+    }
+  ],
+  "base_filter": "type = 'sponsored'",
+  "check_constraints": [
+    {
+      "attribute": [
+        "price"
+      ],
+      "base_filter": "type = 'sponsored'",
+      "check": "price > 0",
+      "name": "price_must_be_positive"
+    }
+  ],
+  "custom_indexes": [
+    {
+      "all_tenants?": false,
+      "concurrently": true,
+      "error_fields": [
+        "uniq_custom_one",
+        "uniq_custom_two"
+      ],
+      "fields": [
+        {
+          "type": "atom",
+          "value": "uniq_custom_one"
+        },
+        {
+          "type": "atom",
+          "value": "uniq_custom_two"
+        }
+      ],
+      "include": null,
+      "message": "dude what the heck",
+      "name": null,
+      "nulls_distinct": true,
+      "prefix": null,
+      "table": null,
+      "unique": true,
+      "using": null,
+      "where": null
+    }
+  ],
+  "custom_statements": [],
+  "has_create_action": true,
+  "hash": "8254859F1DED84E83F9565AB104579D5DEF7B9C756EFC3A2F156CC614B87164F",
+  "identities": [
+    {
+      "all_tenants?": false,
+      "base_filter": "type = 'sponsored'",
+      "index_name": "posts_uniq_if_contains_foo_index",
+      "keys": [
+        {
+          "type": "atom",
+          "value": "uniq_if_contains_foo"
+        }
+      ],
+      "name": "uniq_if_contains_foo",
+      "nils_distinct?": true,
+      "where": "(uniq_if_contains_foo LIKE '%foo%')"
+    },
+    {
+      "all_tenants?": false,
+      "base_filter": "type = 'sponsored'",
+      "index_name": "posts_uniq_on_upper_index",
+      "keys": [
+        {
+          "type": "string",
+          "value": "(UPPER(uniq_on_upper))"
+        }
+      ],
+      "name": "uniq_on_upper",
+      "nils_distinct?": true,
+      "where": null
+    },
+    {
+      "all_tenants?": false,
+      "base_filter": "type = 'sponsored'",
+      "index_name": "posts_uniq_one_and_two_index",
+      "keys": [
+        {
+          "type": "atom",
+          "value": "uniq_one"
+        },
+        {
+          "type": "atom",
+          "value": "uniq_two"
+        }
+      ],
+      "name": "uniq_one_and_two",
+      "nils_distinct?": true,
+      "where": null
+    }
+  ],
+  "multitenancy": {
+    "attribute": null,
+    "global": null,
+    "strategy": null
+  },
+  "repo": "Elixir.AshPostgres.TestRepo",
+  "schema": null,
+  "table": "posts"
+}
\ No newline at end of file
diff --git a/priv/resource_snapshots/test_repo/string_points/20250313112823.json b/priv/resource_snapshots/test_repo/string_points/20250313112823.json
new file mode 100644
index 00000000..cfdf889c
--- /dev/null
+++ b/priv/resource_snapshots/test_repo/string_points/20250313112823.json
@@ -0,0 +1,44 @@
+{
+  "attributes": [
+    {
+      "allow_nil?": false,
+      "default": "nil",
+      "generated?": false,
+      "primary_key?": true,
+      "references": null,
+      "size": null,
+      "source": "id",
+      "type": "text"
+    }
+  ],
+  "base_filter": null,
+  "check_constraints": [],
+  "custom_indexes": [],
+  "custom_statements": [],
+  "has_create_action": true,
+  "hash": "43DADF8B94BBDBD802AE3D70ED67791CC968478B7EE6AEBE5B5F8F676DB323BE",
+  "identities": [
+    {
+      "all_tenants?": false,
+      "base_filter": null,
+      "index_name": "string_points_id_index",
+      "keys": [
+        {
+          "type": "atom",
+          "value": "id"
+        }
+      ],
+      "name": "id",
+      "nils_distinct?": true,
+      "where": null
+    }
+  ],
+  "multitenancy": {
+    "attribute": null,
+    "global": null,
+    "strategy": null
+  },
+  "repo": "Elixir.AshPostgres.TestRepo",
+  "schema": null,
+  "table": "string_points"
+}
\ No newline at end of file
diff --git a/priv/test_repo/migrations/20250313112823_migrate_resources51.exs b/priv/test_repo/migrations/20250313112823_migrate_resources51.exs
new file mode 100644
index 00000000..fe51caf5
--- /dev/null
+++ b/priv/test_repo/migrations/20250313112823_migrate_resources51.exs
@@ -0,0 +1,67 @@
+defmodule AshPostgres.TestRepo.Migrations.MigrateResources51 do
+  @moduledoc """
+  Updates resources based on their most recent snapshots.
+
+  This file was autogenerated with `mix ash_postgres.generate_migrations`
+  """
+
+  use Ecto.Migration
+
+  def up do
+    create table(:string_points, primary_key: false) do
+      add(:id, :text, null: false, primary_key: true)
+    end
+
+    create(unique_index(:string_points, [:id], name: "string_points_id_index"))
+
+    create table(:points, primary_key: false) do
+      add(:id, {:array, :float}, null: false, primary_key: true)
+    end
+
+    create(unique_index(:points, [:id], name: "points_id_index"))
+
+    alter table(:posts) do
+      add(:string_point, :text)
+
+      add(
+        :db_point_id,
+        references(:points,
+          column: :id,
+          name: "posts_db_point_id_fkey",
+          type: {:array, :float},
+          prefix: "public"
+        )
+      )
+
+      add(
+        :db_string_point_id,
+        references(:string_points,
+          column: :id,
+          name: "posts_db_string_point_id_fkey",
+          type: :text,
+          prefix: "public"
+        )
+      )
+    end
+  end
+
+  def down do
+    drop(constraint(:posts, "posts_db_point_id_fkey"))
+
+    drop(constraint(:posts, "posts_db_string_point_id_fkey"))
+
+    alter table(:posts) do
+      remove(:db_string_point_id)
+      remove(:db_point_id)
+      remove(:string_point)
+    end
+
+    drop_if_exists(unique_index(:points, [:id], name: "points_id_index"))
+
+    drop(table(:points))
+
+    drop_if_exists(unique_index(:string_points, [:id], name: "string_points_id_index"))
+
+    drop(table(:string_points))
+  end
+end
diff --git a/test/support/domain.ex b/test/support/domain.ex
index c2d867a7..8af874e4 100644
--- a/test/support/domain.ex
+++ b/test/support/domain.ex
@@ -32,6 +32,8 @@ defmodule AshPostgres.Test.Domain do
     resource(AshPostgres.Test.PostFollower)
     resource(AshPostgres.Test.StatefulPostFollower)
     resource(AshPostgres.Test.PostWithEmptyUpdate)
+    resource(AshPostgres.Test.DbPoint)
+    resource(AshPostgres.Test.DbStringPoint)
   end
 
   authorization do
diff --git a/test/support/resources/db_point.ex b/test/support/resources/db_point.ex
new file mode 100644
index 00000000..25b9ca93
--- /dev/null
+++ b/test/support/resources/db_point.ex
@@ -0,0 +1,34 @@
+defmodule AshPostgres.Test.DbPoint do
+  @moduledoc false
+  use Ash.Resource,
+    domain: AshPostgres.Test.Domain,
+    data_layer: AshPostgres.DataLayer
+
+  postgres do
+    table("points")
+    repo(AshPostgres.TestRepo)
+  end
+
+  actions do
+    defaults([:read, :destroy])
+
+    create :create do
+      primary?(true)
+      accept([:id])
+      upsert?(true)
+      upsert_identity(:id)
+    end
+  end
+
+  attributes do
+    attribute(:id, AshPostgres.Test.Point) do
+      public?(true)
+      primary_key?(true)
+      allow_nil?(false)
+    end
+  end
+
+  identities do
+    identity(:id, [:id])
+  end
+end
diff --git a/test/support/resources/db_string_point.ex b/test/support/resources/db_string_point.ex
new file mode 100644
index 00000000..8908527b
--- /dev/null
+++ b/test/support/resources/db_string_point.ex
@@ -0,0 +1,34 @@
+defmodule AshPostgres.Test.DbStringPoint do
+  @moduledoc false
+  use Ash.Resource,
+    domain: AshPostgres.Test.Domain,
+    data_layer: AshPostgres.DataLayer
+
+  postgres do
+    table("string_points")
+    repo(AshPostgres.TestRepo)
+  end
+
+  actions do
+    defaults([:read, :destroy])
+
+    create :create do
+      primary?(true)
+      accept([:id])
+      upsert?(true)
+      upsert_identity(:id)
+    end
+  end
+
+  attributes do
+    attribute(:id, AshPostgres.Test.StringPoint) do
+      public?(true)
+      primary_key?(true)
+      allow_nil?(false)
+    end
+  end
+
+  identities do
+    identity(:id, [:id])
+  end
+end
diff --git a/test/support/resources/post.ex b/test/support/resources/post.ex
index 9fb97cdd..098d0ccf 100644
--- a/test/support/resources/post.ex
+++ b/test/support/resources/post.ex
@@ -456,6 +456,7 @@ defmodule AshPostgres.Test.Post do
 
     attribute(:point, AshPostgres.Test.Point, public?: true)
     attribute(:composite_point, AshPostgres.Test.CompositePoint, public?: true)
+    attribute(:string_point, AshPostgres.Test.StringPoint, public?: true)
     attribute(:stuff, :map, public?: true)
     attribute(:list_of_stuff, {:array, :map}, public?: true)
     attribute(:uniq_one, :string, public?: true)
@@ -541,6 +542,18 @@ defmodule AshPostgres.Test.Post do
       filter(expr(parent(title) == title and parent(id) != id))
     end
 
+    has_many :posts_with_matching_point, __MODULE__ do
+      public?(true)
+      no_attributes?(true)
+      filter(expr(parent(point) == point and parent(id) != id))
+    end
+
+    has_many :posts_with_matching_string_point, __MODULE__ do
+      public?(true)
+      no_attributes?(true)
+      filter(expr(parent(string_point) == string_point and parent(id) != id))
+    end
+
     has_many(:comments, AshPostgres.Test.Comment, destination_attribute: :post_id, public?: true)
 
     has_one :latest_comment, AshPostgres.Test.Comment do
@@ -658,6 +671,18 @@ defmodule AshPostgres.Test.Post do
     end
 
     has_many(:permalinks, AshPostgres.Test.Permalink)
+
+    belongs_to :db_point, AshPostgres.Test.DbPoint do
+      public?(true)
+      allow_nil?(true)
+      attribute_type(AshPostgres.Test.Point)
+    end
+
+    belongs_to :db_string_point, AshPostgres.Test.DbStringPoint do
+      public?(true)
+      allow_nil?(true)
+      attribute_type(AshPostgres.Test.StringPoint)
+    end
   end
 
   validations do
diff --git a/test/support/types/string_point.ex b/test/support/types/string_point.ex
new file mode 100644
index 00000000..0550a904
--- /dev/null
+++ b/test/support/types/string_point.ex
@@ -0,0 +1,60 @@
+defmodule AshPostgres.Test.StringPoint do
+  @moduledoc false
+  use Ash.Type
+
+  defstruct [:x, :y, :z]
+
+  @type t :: %__MODULE__{
+          x: float(),
+          y: float(),
+          z: float()
+        }
+
+  def storage_type(_), do: :string
+
+  def cast_input(nil, _), do: {:ok, nil}
+
+  def cast_input(%__MODULE__{} = a, _) do
+    {:ok, a}
+  end
+
+  def cast_input({x, y, z}, _) when is_float(x) and is_float(y) and is_float(z) do
+    {:ok, %__MODULE__{x: x, y: y, z: z}}
+  end
+
+  def cast_input(enc, _) when is_binary(enc) do
+    {:ok, parse!(enc)}
+  end
+
+  def cast_input(_, _), do: :error
+
+  def cast_stored(nil, _), do: {:ok, nil}
+
+  def cast_stored(enc, _) when is_binary(enc) do
+    {:ok, parse!(enc)}
+  end
+
+  def cast_stored(_, _) do
+    :error
+  end
+
+  def dump_to_native(nil, _), do: {:ok, nil}
+
+  def dump_to_native(%__MODULE__{x: x, y: y, z: z}, _) do
+    enc = Enum.map_join([x, y, z], ",", &Float.to_string/1)
+
+    {:ok, enc}
+  end
+
+  def dump_to_native(_, _) do
+    :error
+  end
+
+  defp parse!(enc) when is_binary(enc) do
+    [x, y, z] =
+      String.split(enc, ",")
+      |> Enum.map(&String.to_float/1)
+
+    %__MODULE__{x: x, y: y, z: z}
+  end
+end
diff --git a/test/type_test.exs b/test/type_test.exs
index 856a2da3..39a809e8 100644
--- a/test/type_test.exs
+++ b/test/type_test.exs
@@ -51,4 +51,53 @@ defmodule AshPostgres.Test.TypeTest do
              |> Ash.Query.filter(point == ^{1.0, 2.0, 3.0})
              |> Ash.read!()
   end
+
+  test "complex custom types can be used in relationships" do
+    [p | _] =
+      for _ <- 1..4//1 do
+        Post
+        |> Ash.Changeset.for_create(:create, %{
+          point: {1.0, 2.0, 3.0},
+          string_point: "1.0,2.0,3.0"
+        })
+        |> Ash.create!()
+      end
+
+    p = p |> Ash.load!([:posts_with_matching_point, :posts_with_matching_string_point])
+
+    assert Enum.count(p.posts_with_matching_point) == 3
+    assert Enum.count(p.posts_with_matching_string_point) == 3
+
+    %{id: id} =
+      Post
+      |> Ash.Changeset.for_create(:create)
+      |> Ash.Changeset.manage_relationship(:db_point, %{id: {2.0, 3.0, 4.0}}, type: :create)
+      |> Ash.create!()
+
+    [p] =
+      Post
+      |> Ash.Query.for_read(:read)
+      |> Ash.Query.load(:db_point)
+      |> Ash.Query.filter(id == ^id)
+      |> Ash.read!()
+
+    assert p.db_point_id == {2.0, 3.0, 4.0}
+    assert p.db_point.id == {2.0, 3.0, 4.0}
+
+    %{id: id} =
+      Post
+      |> Ash.Changeset.for_create(:create)
+      |> Ash.Changeset.manage_relationship(:db_string_point, %{id: "2.0,3.0,4.0"}, type: :create)
+      |> Ash.create!()
+
+    [p] =
+      Post
+      |> Ash.Query.for_read(:read)
+      |> Ash.Query.load(:db_string_point)
+      |> Ash.Query.filter(id == ^id)
+      |> Ash.read!()
+
+    assert p.string_point_id == %{x: 2.0, y: 3.0, z: 4.0}
+    assert p.string_point.id == %{x: 2.0, y: 3.0, z: 4.0}
+  end
 end