SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 2)
    Function CAST (alias x) (children 1)
     ExpressionList (children 2)
      Function if (children 1)
       ExpressionList (children 3)
        Function equals (children 1)
         ExpressionList (children 2)
          Literal UInt64_1
          Literal UInt64_0
        Function toNullable (children 1)
         ExpressionList (children 1)
          Function toInt8 (children 1)
           ExpressionList (children 1)
            Literal UInt64_3
        Literal NULL
      Literal \'Int32\'
    Function toTypeName (children 1)
     ExpressionList (children 1)
      Identifier x