[Koha] Export between two catalog inside 'Staff Client'

Hello, Koha-users ! In my library computer (OS Windows XP), Koha 3.14 works as a 'staff client'. In this computer I have created 2 bibliographic catalogues, named B1 and B2, with identical UKRMARC framewokrs. It is necessary to export database B1 into B2. What option must I choose (among 'Export to CSV Spreadsheet', 'Export to Excel as xml format', 'Export to OpenDocument Spreadsheet format', 'Export to SQL', see: Administration > 4.1.5.1. Export Framework ) to export database B1 into B2 ? Why ? Thank you, Gennady