SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 2)
   ExpressionList (children 1)
    Function if (children 1)
     ExpressionList (children 3)
      Function isNull (children 1)
       ExpressionList (children 1)
        Identifier x
      Literal NULL
      Function intDiv (children 1)
       ExpressionList (children 2)
        Literal UInt64_42
        Identifier x
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      Subquery (children 1)
       SelectWithUnionQuery (children 1)
        ExpressionList (children 1)
         SelectQuery (children 1)
          ExpressionList (children 1)
           Function CAST (alias x) (children 1)
            ExpressionList (children 2)
             Function materialize (children 1)
              ExpressionList (children 1)
               Literal NULL
             Literal \'Nullable(Int64)\'