SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 2)
    Function toUInt32OrZero (children 1)
     ExpressionList (children 1)
      Literal \'123a\'
    Function toUInt32OrZero (children 1)
     ExpressionList (children 1)
      Literal \'456\'
