Value Mapping: maintainability

Hi,

Can anyone give me some advice on the best way of performing transcodifications in XI. Is there a clear best option between Value Mappings and a database accessed via JDBC?

- we have a lot of IDoc to legacy interfaces to build with various values to map - stuff like unit of measure codes, customer numbers and material codes.

- mappings are done both in Java and in the Graphical Tool(with Java functions).

I'm not so keen on value mappings because they seem difficult to maintain - I prefer something users can update themselves.

Is it possible to use tables in the XI database and access these via Java? That way we could use SM30 to maintain the tables.

Any opinions/advice would be gratefully received.

Thanks,

Paul