How can I have a Setup project not copy files from the CD if they already exist?

Visual Basic 2005 Professional Edition:

I am using a Setup project to deploy my application. It also installs a few SQL database tables. But, if the user is installing an update, the files are replacing his files and he is losing his data. I specified 'copy if newer' in the .mdf file properties.

How can I have it not copy the files from the CD if they already exist?

[389 byte] By [furjaw] at [2007-12-24]