Wie exportiere ich MySQL-Daten mit PHP in separate Excel-Zellen?

<?php
// MySQL connection details
$DB_Server = "localhost";
$DB_Username = "username";
$DB_Password = "password";
$DB_DBName = "databasename";
$DB_TBLName = "tablename";

// Define Excel file name
$filename = "exportfile.xls";

// Connect to MySQL
$Connect = @mysql_connect($DB_Server, $DB_Username, $DB_Password) or die("Couldn't connect to MySQL: " . mysql_error());

// Select database
$Db = @mysql_select_db($DB_DBName, $Connect) or die("Couldn't select database: " . mysql_error());

// Execute query
$sql = "SELECT * FROM $DB_TBLName";
$result = @mysql_query($sql, $Connect) or die("Couldn't execute query: " . mysql_error());

// Set CSV separator (tabs)
$sep = "\t";

// Print column names as headers
for ($i = 0; $i < mysql_num_fields($result); $i++) {
    echo mysql_field_name($result, $i) . $sep;
}
echo "\n";

// Print data rows
while ($row = mysql_fetch_row($result)) {
    $line = '';

    for ($j = 0; $j < mysql_num_fields($result); $j++) {
        if (empty($row[$j])) {
            $line .= "NULL" . $sep;
        } else {
            $line .= '"' . str_replace('"', '""', $row[$j]) . '"' . $sep;
        }
    }

    $line = trim($line);
    echo $line . "\n";
}

// Close MySQL connection
mysql_close($Connect);

// Set file headers for Excel
header("Content-Type: application/vnd.ms-excel");
header("Content-Disposition: attachment; filename=$filename");
header("Pragma: no-cache");
header("Expires: 0");

// Echo data to Excel file
echo $line . "\n";