magento_deletedbprefix.php

<?php

$database_host      = "localhost";
$database_user      = "username";
$database_password  = "password";
$magento_database   = "databasename";
$table_prefix       = "prefixhere_";
$dryrun				= true; // change to false when you want to commit changes

$db = mysql_connect($database_host, $database_user, $database_password);
mysql_select_db($magento_database);

$query = "SHOW TABLES";
$result = mysql_query($query) or die('### Error cannot connect to DB');

if ($dryrun) { echo "### No changes made, just testing <br />"; }

while($row = mysql_fetch_array($result)) {
	$old_table = $row[0];
	if ($new_table = preg_replace('/^'.$table_prefix.'/', '', $old_table)) {
		if ($new_table != $old_table ) {
			echo "Rename: " . $old_table . ", to: ". $new_table;
			if (!$dryrun) {
				$query = "RENAME TABLE `$old_table` TO `$new_table`";
				mysql_query($query);
				echo " -> DONE <br />";
			} else { echo " -> Just checking <br />"; }
		} else {
			echo "Nothing to rename: " . $old_table  . "<br />";
		}
    }
}

?>