Functionality Improvement.
You are now able to retrieve any error messages returned by the database after a query has been run. To make use of this function you can do the following:
$res = $db -> query ( “SELECT `hello` FROM `donotexist`” );
echo ( $db -> retrieveErrorMessage ( $res ) ); //This will only display the error message
or
print_r ( $db -> retrieveErrorMessage ( $res, FALSE ) ); //This will print out the entire exception object (click here for information on exceptions)