I’m doing an import (from one version of a data file to another), and realise that, having opened the source file, I then need to show all records in all tables before the import, otherwise the import will only import found sets from the source file.
You've almost answered your question.
Don't have the import file open. If you select the file to import from and do not explicitly open it then it is not open.
Thanks Malcolm, that's helped me sort this out. I had tried doing the import without opening the file first, but found that I had to provide username/password for each table encountered by the import script. The solution, it seems, is to set "Log in using..." for the source file - everything now works fine.