If it was fresh installation you can reinstall it and them database will be created again.
However if you able to see front page or admin login page it means that database may be still there and you looked at the wrong place.
If yo uwant to reinstall it without reuploading files then using your FTP client, open the magento root on your server and go to app/etc folder and delete the local.xml file
Then open front page and ther ewill be installation wizard.
Thanks