I have just made a copy of a working website over to a different domain name. I copied the structure of the original database and some of the important data.
However, when I upload the files to the new website I get the following error message:
1046 - No database selected

select configuration_key as cfgKey, configuration_value as cfgValue from configuration

[TEP STOP]
Any ideas what is causing this?

I created a database user, set the password in the cpanelX  MySQL Account Maintenance screen, and used the same username and password in the include/configure.php file as follows:
  define('DB_SERVER_USERNAME', 'USERNAME');
  define('DB_SERVER_PASSWORD', 'PASSWORD');
Do I need to put this information somewhere else as well?

http://www.lunarforums.com/forum/index.php?topic=21575.0

see this thread.

Hi. Did you copy it to another domain on the same a ccount or a new account? We would need to know the domain names involved to help too. Be sure for the database name and username, you added the cpanel username_ to the beginning of them in your configure files. They should look exactly as you see in Cpanel, Mysql and the user must be added to the database.

If this is for oscommerce, there are 2 files to put them in; includes/configure.php and admin/includes/configure.php