>>When a table is added to a DBC it is linked with a unique id. One cannot overwrite an old table with a new one by the same name because the ids won't match and the DBC will complain.
>>Question: What is the best method to update an EXE of an previously installed app without overwriting the old data tables (hence, the data)?
>
>I put my non-data application files in a subdirectory of my development tree called "PROD" (production). I then create my setup files starting in this directory. This prevents any inclusion of data files. I can also mimick my application tree under this subdirectory if needed.

Thanks Mark, and the others who contributed! (UT is the best support system in existance!)
This sounds like the approach I want to take. Copying the EXE will work only when users are accessing from a network installed app, which is a method I already use. But, some users will be installing the app onto standalones using the DISK144 method, and I am not comfortable with them dragging the EXE from a floppy if they didn't do the normal install. The idea about using the ALTER TABLE command in a preinstall EXE sounds neat too!

Jerry