Website program problem

Hi

I have had a website built and then lost contact with developer of site wondering if anyone can help sort the problem out :

Error message on the site is:

Warning: mysql_select_db(): supplied argument is not a valid MySQL-Link resource in /hsphere/local/home/cvrecruit123/cvrecruit.ie/lib/class.database.php on line 53 Warning: mysql_query(): supplied argument is not a valid MySQL-Link resource in /hsphere/local/home/cvrecruit123/cvrecruit.ie/lib/class.database.php on line 230 Warning: mysql_errno(): supplied argument is not a valid MySQL-Link resource in /hsphere/local/home/cvrecruit123/cvrecruit.ie/lib/class.database.php on line 232 Warning: mysql_error(): supplied argument is not a valid MySQL-Link resource in /hsphere/local/home/cvrecruit123/cvrecruit.ie/lib/class.database.php on line 233

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