you could use embedded SQL to talk to diffrent systems in one programm just switch from connection to another with set connection.
Writing data from a remote database to a local file, isn’t really new, interactive SQL and QMQUERY have this feature since a couple of years and releases.
The ARDPGM interfaces was used by Oracles DB2 adapter (they stopped support) and currently it is used by ArdGate and Razlees DBGATE to enable access with the native SQL interfaces of AS/400 to remote databases of diffrent flavour. The access to these databases is made by JDBC. DBU uses JDBC for access too, but uses proprietary interfaces (you have to call some routines to access a remote database). This is rather close to Scotts JDBCR4 service programm. Some other solutions are using ODBC and as this drivers don’t work on AS/400, they need another box acting as a kind of Gateway. Most JDBC based solutions are starting up a JVM within each job accessing a remote database; this limits scalability. ArdGate has a diffrent architecture, one prestarted JVM serves multiple client jobs in a multithreaded environment, so it’s fast from the very first connect and it scales very well.