add integration test

Author: karyna-t

dev/tests/integration/testsuite/Magento/Framework/DB/Adapter/Pdo/MysqlTest.php

@@ -34,6 +34,37 @@ protected function tearDown(): void
         restore_error_handler();
     }
 
+    /**
+     * Check PDO stringify fetches options
+     */
+    public function testStringifyFetches(): void
+    {
+        $tableName = $this->resourceConnection->getTableName('table_with_int_column');
+        $columnId = 'integer_column';
+        $adapter = $this->getDbAdapter();
+
+        $table = $adapter
+            ->newTable($tableName)
+            ->addColumn($columnId, Table::TYPE_INTEGER);
+        $adapter->createTable($table);
+        $adapter->insert($tableName, [$columnId => 100]);
+
+        $select = $adapter->select()
+            ->from($tableName)
+            ->columns([$columnId])
+            ->limit(1);
+        $result = $adapter->fetchOne($select);
+
+        $isStringify = $adapter->getConfig()['driver_options'][\PDO::ATTR_STRINGIFY_FETCHES] ?? null;
+        if ($isStringify || $isStringify === null) {
+            $this->assertIsString($result);
+        } else { // option is set to False
+            $this->assertIsInt($result);
+        }
+
+        $adapter->dropTable($tableName);
+    }
+
     /**
      * Test lost connection re-initializing
      *