database connection on crystal report

I have designed a report using crystal report.
In crystal report you should hardcode to point somewhere your database located e.g. c:\abc\abc.mdb
I use VB with Crystal Report activex control to call the crystal report xxx.rpt file. And this application is need to disbute to users. Then when user install my application and the database *.mdb located at different directory that
the *.rpt pointed to. As a result there may have error from crystal report that cannot found *.mdb or no data in the report.
Of course I can open the .rpt file to change the location of the dataabse the user will installed to. But it is not really feasible.

How do the report file know the database location ?
I think this must do with coding but i don't know