5 files changed, 18 insertions, 1 deletions
diff --git a/activerecord/CHANGELOG.md b/activerecord/CHANGELOG.md
index bae2cab457..f8fa71c60b 100644
--- a/activerecord/CHANGELOG.md
+++ b/activerecord/CHANGELOG.md
@@ -1,3 +1,7 @@
+*   Fix inspection behavior when the :id column is not primary key.
+
+    *namusyaka*
+
 *   Deprecate locking records with unpersisted changes.
 
     *Marc Schütz*
diff --git a/activerecord/lib/active_record/attribute_methods/read.rb b/activerecord/lib/active_record/attribute_methods/read.rb
index 369a6e35aa..fdc4bf6621 100644
--- a/activerecord/lib/active_record/attribute_methods/read.rb
+++ b/activerecord/lib/active_record/attribute_methods/read.rb
@@ -54,7 +54,7 @@ module ActiveRecord
           attr_name.to_s
         end
 
-        name = self.class.primary_key if name == "id".freeze
+        name = self.class.primary_key if name == "id".freeze && self.class.primary_key
         _read_attribute(name, &block)
       end
 
diff --git a/activerecord/test/cases/primary_keys_test.rb b/activerecord/test/cases/primary_keys_test.rb
index f92ee15cfa..1baf7c4902 100644
--- a/activerecord/test/cases/primary_keys_test.rb
+++ b/activerecord/test/cases/primary_keys_test.rb
@@ -7,6 +7,7 @@ require "models/movie"
 require "models/keyboard"
 require "models/mixed_case_monkey"
 require "models/dashboard"
+require "models/non_primary_key"
 
 class PrimaryKeysTest < ActiveRecord::TestCase
   fixtures :topics, :subscribers, :movies, :mixed_case_monkeys
@@ -89,6 +90,12 @@ class PrimaryKeysTest < ActiveRecord::TestCase
     assert_equal("John Doe", subscriberReloaded.name)
   end
 
+  def test_id_column_that_is_not_primary_key
+    NonPrimaryKey.create!(id: 100)
+    actual = NonPrimaryKey.find_by(id: 100)
+    assert_match %r{<NonPrimaryKey id: 100}, actual.inspect
+  end
+
   def test_find_with_more_than_one_string_key
     assert_equal 2, Subscriber.find(subscribers(:first).nick, subscribers(:second).nick).length
   end
diff --git a/activerecord/test/models/non_primary_key.rb b/activerecord/test/models/non_primary_key.rb
new file mode 100644
index 0000000000..1cafb09608
--- /dev/null
+++ b/activerecord/test/models/non_primary_key.rb
@@ -0,0 +1,2 @@
+class NonPrimaryKey < ActiveRecord::Base
+end
diff --git a/activerecord/test/schema/schema.rb b/activerecord/test/schema/schema.rb
index 08ff0336b9..d1acf4524f 100644
--- a/activerecord/test/schema/schema.rb
+++ b/activerecord/test/schema/schema.rb
@@ -1039,6 +1039,10 @@ ActiveRecord::Schema.define do
   create_table :test_with_keyword_column_name, force: true do |t|
     t.string :desc
   end
+
+  create_table :non_primary_keys, force: true, id: false do |t|
+    t.integer :id
+  end
 end
 
 Course.connection.create_table :courses, force: true do |t|