We have Oracle as database, version 19.x set in Timezone GMT+2 We are running hibernate with TimeZone Europe/Stockholm set. Column holding Instant is TIMESTAMP.

Saving and Getting dateValues does not work as expected.
If you save an entity with the time: 2023-08-09T03:08:11.063446900Z
And then try to get entities within a period of time:
2023-08-09T02:08:11.063446900Z - 2023-08-09T04:08:11.063446900Z
No entities are found.

If you set the "hibernate.type.preferred_instant_jdbc_type" to TIMESTAMP, then test will run OK. If you keep it to default, that is TIMESTAMP_UTC, test will fail, no entity will be found.

Link to testcase: Test Case