SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 2)
   ExpressionList (children 2)
    Literal \'aes-256-ecb\' (alias mode)
    Literal \'test_key________________________\' (alias key)
   ExpressionList (children 2)
    Identifier mode
    Function hex (children 1)
     ExpressionList (children 1)
      Function encrypt (children 1)
       ExpressionList (children 3)
        Identifier mode
        Function toNullable (children 1)
         ExpressionList (children 1)
          Literal \'Hello World!\'
        Identifier key