SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 2)
    Function CAST (alias v) (children 1)
     ExpressionList (children 2)
      Literal \'abc\'
      Literal \'Variant(String, UInt64)\'
    Function variantType (children 1)
     ExpressionList (children 1)
      Identifier v
