>Georges,
>What is the difference between open the table(s) and modify DE at tun time?
>I think:

The DE takes care of opening and closing the tables. When changing the path to the tables you have to close the tables (.DATAENVIRONMENT.CLOSETABLES()), change the cursorsource of each table in the DE and reopen the tables (.DATAENVIRONMENT.OPENTABLES()). See the mentioned paper for the details. In my applications I store a pathvariable as a property of each cursor. The new path to the table is stored in this variable. This way all the tables have not to reside in the same folder.