OK ... excitement is mounting as you fire up your new database system - (pause) - but what about all your
legacy data?
These days I suspect it is quite rare for a database to start off with a "clean sheet", as it were. In most cases there will be perhaps thousands of records - probably representing
years of work - that need to be preserved, and "brought across" to, and integrated into, the new system.
But ... how's it done? And how much time (and effort) is involved?
For what it's worth, I believe that this rather important step in commissioning a new database system may sometimes be a bit, shall we say, overlooked!

As mentioned
elsewhere, my own approach is basically to get the legacy data into an Excel spreadsheet, spend some time (time well spent, in fact) cleaning it up then saving as a .csv file, before importing into a native datafile (.dbf) for cleaning up and further processing by "the system".
How do commercially available systems go about this, I wonder? Can it be done simply "at the touch of a button"?

By the way (like most other interesting topics), this has been touched on
before.