diff --git a/group.install b/group.install
index 49d1dd4..470626a 100644
--- a/group.install
+++ b/group.install
@@ -10,6 +10,7 @@ use Drupal\Core\Config\ExtensionInstallStorage;
 use Drupal\Core\Config\InstallStorage;
 use Drupal\Core\Entity\EntityTypeListenerInterface;
 use Drupal\Core\Entity\Sql\SqlContentEntityStorage;
+use Drupal\Core\Field\BaseFieldDefinition;
 
 /**
  * Resave all GroupContent labels and remove orphaned entities.
@@ -424,3 +425,61 @@ function group_update_8014() {
     $group_type->save(TRUE);
   }
 }
+
+
+/**
+ * alter the `group_content_field_data` table to change entity_id to VARCHAR(32)
+ */
+function group_update_8015() {
+	$database = Drupal::database();
+	$entity_type = 'group_content';
+	$table = 'group_content_field_data';
+	$field_name = 'entity_id';
+
+	$rows = NULL;
+	if ($database->schema()->tableExists($table)) {
+		// The table data to restore after the update is completed.
+		$rows = $database->select($table, 'pm')
+			->fields('pm')
+			->execute()
+			->fetchAll();
+	}
+
+	$database->truncate($table)->execute();
+
+	$entity_definition_update_manager = Drupal::entityDefinitionUpdateManager();
+
+	// Delete the storage definition if it was defined before.
+	$storage_definition = $entity_definition_update_manager->getFieldStorageDefinition($field_name, $entity_type);
+	$entity_definition_update_manager->uninstallFieldStorageDefinition($storage_definition);
+
+	// Add content_translation_changed field.
+	$new_field_storage = BaseFieldDefinition::create('entity_reference')
+		->setLabel(t('Content'))
+		->setDescription(t('The entity to add to the group.'))
+		->setSetting('target_type', 'group_type')
+		->setDisplayOptions('form', [
+			'type' => 'entity_reference_autocomplete',
+			'weight' => 5,
+			'settings' => [
+				'match_operator' => 'CONTAINS',
+				'size' => '60',
+				'placeholder' => '',
+			],
+		])
+		->setDisplayConfigurable('view', TRUE)
+		->setDisplayConfigurable('form', TRUE)
+		->setRequired(TRUE);
+
+	$entity_definition_update_manager->installFieldStorageDefinition('entity_id', $entity_type, 'group', $new_field_storage);
+
+	// Restore existing data in the same table.
+	if (!is_null($rows)) {
+		foreach ($rows as $row) {
+			$database->insert($table)
+				->fields((array) $row)
+				->execute();
+		}
+	}
+
+}
\ No newline at end of file