Converter um Array para arquivo CSV em PHP - http://www.marcelotorresweb.com/converter-um-array-para-arquivo-csv-em-php/

array_to_csv_download.php

<?php
/**
 ** convert input array to a csv file and force downlaod the same
 **
 ** should be called before any output is send to the browser
 ** input array should be an associative array
 ** the key of the associative array will be first row of the csv file
 ** 
 ** @link http://perials.com/php-function-convert-array-csv-file-download/ Original post - Php function to convert an array to CSV file for download
 ** @param array $array
 ** @return null
 **/
function array_to_csv_download(array $array) {
    
    if (count($array) == 0) {
        return null;
    }
    
    $filename = "data_export_" . date("Y-m-d") . ".csv";
    // disable caching
    $now = gmdate("D, d M Y H:i:s");
    header("Expires: Tue, 03 Jul 2001 06:00:00 GMT");
    header("Cache-Control: max-age=0, no-cache, must-revalidate, proxy-revalidate");
    header("Last-Modified: {$now} GMT");
 
    // force download  
    header("Content-Type: application/force-download");
    header("Content-Type: application/octet-stream");
    header("Content-Type: application/download");
 
    // disposition / encoding on response body
    header("Content-Disposition: attachment;filename={$filename}");
    header("Content-Transfer-Encoding: binary");
 
    $df = fopen("php://output", 'w');
    fputcsv($df, array_keys(reset($array)));
    foreach ($array as $row) {
        fputcsv($df, $row);
    }
    fclose($df);
    die();    
}

use_array_to_csv_download.php

<?php
$array_recordset = array(
                    array('id'=>'560','name'=>'John','age'=>'31','occupation'=>'Designer'),
                    array('id'=> '561','name'=>'Robert','age'=>'21','occupation'=>'Student')
                );
                
array_to_csv_download($array_recordset);