diff --git a/app/code/Magento/ConfigurableProduct/Model/ResourceModel/Product/Type/Configurable.php b/app/code/Magento/ConfigurableProduct/Model/ResourceModel/Product/Type/Configurable.php
index feffd22a0fb3d..c87611e24092c 100644
--- a/app/code/Magento/ConfigurableProduct/Model/ResourceModel/Product/Type/Configurable.php
+++ b/app/code/Magento/ConfigurableProduct/Model/ResourceModel/Product/Type/Configurable.php
@@ -17,7 +17,6 @@
 use Magento\ConfigurableProduct\Model\ResourceModel\Attribute\OptionProvider;
 use Magento\Framework\App\ScopeResolverInterface;
 use Magento\Framework\App\ObjectManager;
-use Magento\Framework\DB\Adapter\AdapterInterface;
 
 /**
  * Configurable product resource model.
@@ -160,9 +159,11 @@ public function saveProducts($mainProduct, array $productIds)
      */
     public function getChildrenIds($parentId, $required = true)
     {
-        $select = $this->getConnection()->select()->from(
+        $connection = $this->getConnection();
+
+        $select = $connection->select()->from(
             ['l' => $this->getMainTable()],
-            ['product_id', 'parent_id']
+            ['product_id', 'p.entity_id as parent_id']
         )->join(
             ['p' => $this->getTable('catalog_product_entity')],
             'p.' . $this->optionProvider->getProductEntityLinkField() . ' = l.parent_id',
@@ -176,13 +177,12 @@ public function getChildrenIds($parentId, $required = true)
             $parentId
         );
 
-        $childrenIds = [
-            0 => array_column(
-                $this->getConnection()->fetchAll($select),
-                'product_id',
-                'product_id'
-            )
-        ];
+        $childrenIds = [0 => []];
+        foreach ($connection->fetchAll($select) as $row) {
+            $childrenIds[$row['parent_id']][] = $row['product_id'];
+            // Alternative format for backward compatibility
+            $childrenIds[0][$row['product_id']] = $row['product_id'];
+        }
 
         return $childrenIds;
     }
diff --git a/dev/tests/integration/testsuite/Magento/ConfigurableProduct/Model/Product/Type/ConfigurableTest.php b/dev/tests/integration/testsuite/Magento/ConfigurableProduct/Model/Product/Type/ConfigurableTest.php
index 0d2043434d359..913168b87ff7c 100644
--- a/dev/tests/integration/testsuite/Magento/ConfigurableProduct/Model/Product/Type/ConfigurableTest.php
+++ b/dev/tests/integration/testsuite/Magento/ConfigurableProduct/Model/Product/Type/ConfigurableTest.php
@@ -555,7 +555,7 @@ public function testSaveProductRelationsOneChild()
         self::assertNotEmpty($oldChildrenIds);
         self::assertNotEmpty($oneChildId);
 
-        $product = $this->productRepository->getById($this->product->getId());
+        $product = $this->productRepository->getById(1);
 
         $extensionAttributes = $product->getExtensionAttributes();
         $extensionAttributes->setConfigurableProductLinks([$oneChildId]);
@@ -563,13 +563,17 @@ public function testSaveProductRelationsOneChild()
 
         $this->productRepository->save($product);
 
-        self::assertEquals(
-            [
-                [
-                    $oneChildId => $oneChildId
-                ]
-            ],
-            $this->model->getChildrenIds($this->product->getId())
+        // Check alternative format for backward compatibility
+        $expectedArray[0] = [
+            $oneChildId => $oneChildId
+        ];
+        //Check grouped array, ex
+        //array(group => array(ids))
+        $expectedArray[$product->getId()][] = $oneChildId;
+
+        self::assertSame(
+            $expectedArray,
+            $this->model->getChildrenIds($product->getId())
         );
     }