ODKU of non-versioning column inserts history row

create table t1 (

  x int unique,

  y int without system versioning

) with system versioning;

insert into t1 (x, y) values ('1', '1');

insert into t1 (x, y) values ('1', '2')

  on duplicate key update y = 3;

select *, row_start, row_end from t1 for system_time all;

drop table t1;

select *, row_start, row_end from t1 for system_time all;

x       y       row_start       row_end

1       3       2023-07-19 12:38:44.171889      2038-01-19 06:14:07.999999

1       1       2023-07-19 12:38:44.171889      2023-07-19 12:38:44.172925

select *, row_start, row_end from t1 for system_time all;

x       y       row_start       row_end

1       3       2023-07-19 12:38:44.171889      2038-01-19 06:14:07.999999