If you did not enable createdDate already. The value will be missing indeed.
What you can do is:
- Write an ASU or some way of migrating the existing data – could also be a screen with datagrid and action buttons
- You can start filling the created date manually to a valid value if you knew when the object was created
- May be if there are any associated objects with created date filled, you can also choose to use that date
I dont think there are any mechanism available to make this filled automatically.
The values of systems members like CreatedDate, changedDate etc cannot be changed using a change activity in a microflow.
The only option I see is to directly edit them in the database.
If you are running in the Mx cloud:
note; ensure the app is not accesible during this, to avoid data loss