<?php
/* vars for export */
// database record to be exported

$db_record = '2pix';
// optional where query
// filename for export
$csv_filename = 'db_export_'.$db_record.'_'.date('Y-m-d').'.csv';
// database variables
$hostname = "localhost";
$user = "db-user";
$password = "db-pass";
$database = "db-name";
$port = 3306;
$conn = mysqli_connect($hostname, $user, $password, $database, $port);
if (mysqli_connect_errno()) {
    die("Failed to connect to MySQL: " . mysqli_connect_error());
}
mysqli_set_charset($conn,"utf8");
// create empty variable to be filled with export data
$csv_export = '';
// query to get data from database
$query = mysqli_query($conn, "SELECT * from .. WHERE ..");
$field = mysqli_field_count($conn);
// create line with field names
for($i = 0; $i < $field; $i++) {
    $csv_export.= mysqli_fetch_field_direct($query, $i)->name.';';
}
// newline (seems to work both on Linux & Windows servers)
$csv_export.= '
';
// loop through database query and fill export variable
while($row = mysqli_fetch_array($query)) {
    // create line with field values
    for($i = 0; $i < $field; $i++) {
        $csv_export.= '"'.$row[mysqli_fetch_field_direct($query, $i)->name].'";';
    }
    $csv_export.= '
';
}
// Export the data and prompt a csv file for download
header('Content-Encoding: UTF-8');
header('Content-type: text/csv; charset=UTF-8');
header("Content-Disposition: attachment; filename=".$csv_filename."");
echo "\xEF\xBB\xBF"; // UTF-8 BOM
echo($csv_export);