1 files changed, 9 insertions, 0 deletions
diff --git a/activerecord/test/cases/connection_pool_test.rb b/activerecord/test/cases/connection_pool_test.rb
index 27fc3cab49..0727e86705 100644
--- a/activerecord/test/cases/connection_pool_test.rb
+++ b/activerecord/test/cases/connection_pool_test.rb
@@ -38,6 +38,15 @@ module ActiveRecord
         assert_equal 'id', @pool.primary_keys['omgponies']
       end
 
+      def test_primary_key_is_set_on_columns
+        posts_columns = @pool.columns_hash['posts']
+        assert posts_columns['id'].primary
+
+        (posts_columns.keys - ['id']).each do |key|
+          assert !posts_columns[key].primary
+        end
+      end
+
       def test_clear_stale_cached_connections!
         pool = ConnectionPool.new ActiveRecord::Base.connection_pool.spec