Should a Function always Return Something?

[DoubleDee]

Below is a Function that I just created which returns a Section's Name...

    function getSectionName($dbc, $slug){

        // Build query.
        $q1 = "SELECT name
                FROM section
                WHERE slug=?";

        // Prepare statement.
        $stmt1 = mysqli_prepare($dbc, $q1);

        // Bind variable to query.
        mysqli_stmt_bind_param($stmt1, 's', $slug);

        // Execute query.
        mysqli_stmt_execute($stmt1);

        // Store results.
        mysqli_stmt_store_result($stmt1);

        // Check # of Records Returned.
        if (mysqli_stmt_num_rows($stmt1)==1){
            // Section Found.

            // Bind result-set to variables.
            mysqli_stmt_bind_result($stmt1, $sectionName);

            // Fetch record.
            mysqli_stmt_fetch($stmt1);

            // Return Section Name.
            return $sectionName;

        }else{
            // Section Not Found.
            $resultsCode = 'FUNCTION_SECTION_NOT_FOUND_5010';

            // Set Error Source.
            $errorPage = $_SERVER['SCRIPT_NAME'];

            // Log Function Error.
            logError($dbc, $resultsCode, $errorPage);

            // End script.
            exit();

        }//End of CHECK FOR SECTION

    } 

I am wondering if I should return a NULL or '' in the ELSE branch in addition to logging the Error?

If I don't do that, then in my calling script, I would have to check for a Null like this to avoid an error...

    <title><?php echo (isset ($sectionName) ? $sectionName : '') ?> Section</title>

...which seems silly.

Suggestions?

Thanks,


Debbie