我在这里运行db查询，并使用mysqli和MYSQLI_USE_RESULT以更快地执行查询。但是这里需要对数据进行php操作，因此它并不像在返回的每一行上写入CSV文件那么简单。我知道数据库查询正在完成（即使它花了很长时间），但db查询确实完成了，所以问题必须在PHP内存端，因为我得到504网关超时错误。我的代码如下：
global $wpdb, $root_dir;
if (!defined('ABSPATH'))
$root_dir = dirname(__FILE__) . '/';
else
$root_dir = ABSPATH;
require_once($root_dir . 'wp-config.php');
$wp->init();
$wp->parse_request();
$wp->query_posts();
$wp->register_globals();
$start_date = !empty($_GET['start']) ? DateTime::createFromFormat('Y-m-d', $_GET['start']) : '';
$end_date = !empty($_GET['end']) ? DateTime::createFromFormat('Y-m-d', $_GET['end']) : '';
$append = array();
if (!empty($start_date))
$append[] = $start_date->format('Y-m-d');
if (!empty($end_date))
$append[] = $end_date->format('Y-m-d');
$filename = 'user-export' . (!empty($append) ? '_' . implode('_', $append) : '');
header("Cache-Control: must-revalidate, post-check=0, pre-check=0");
header('Content-Description: File Transfer');
header("Content-type: text/csv");
header("Content-Disposition: attachment; filename=\"" . $filename . ".csv\"");
header("Expires: 0");
header("Pragma: public");
ini_set('memory_limit', '-1');
ini_set('max_execution_time', '-1');
set_time_limit(0);
$headers = array('Order Date/Time', 'Name', 'Billing Address', 'Shipping Address', 'Phone', 'Email Address');
$meta_keys = array('_billing_first_name', '_billing_last_name', '_billing_address_1', '_billing_address_2', '_billing_city', '_billing_state', '_billing_postcode', '_billing_email', '_billing_country', '_billing_phone', '_shipping_address_1', '_shipping_address_2', '_shipping_city', '_shipping_state', '_shipping_postcode', '_shipping_country');
$csv_data = $emails = $order_ids_skipped = $meta = array();
// Using an unbuffered query...
$mysqli = new mysqli(DB_HOST, DB_USER, DB_PASSWORD, DB_NAME);
if (mysqli_connect_errno()) {
printf("Connect failed: %s\n", mysqli_connect_error());
exit();
}
$uresult = $mysqli->query("
SELECT p.ID, p.post_date, pm.meta_key, pm.meta_value
FROM {$wpdb->posts} AS p
INNER JOIN {$wpdb->postmeta} AS pm ON (pm.post_id = p.ID AND pm.meta_key IN ('" . implode("','", $meta_keys) . "'))
WHERE p.post_type = 'shop_order' AND p.post_status IN ('wc-sent-delivery', 'wc-awaiting-delivery', 'wc-completed')" . (!empty($start_date) && !empty($end_date) ? " AND (p.post_date >= '" . $start_date->format('Y-m-d') . " 00:00:00' AND p.post_date <= '" . $end_date->format('Y-m-d') . " 23:59:59')" : "") . "
ORDER BY p.post_date DESC", MYSQLI_USE_RESULT);
if ($uresult)
{
while ($order_query = $uresult->fetch_assoc())
{
// If the email already exists, continue...
if ($order_query['meta_key'] == '_billing_email' && !empty($emails) && in_array($order_query['meta_value'], $emails))
{
if (isset($csv_data[$order_query['ID']]))
unset($csv_data[$order_query['ID']]);
if (isset($meta[$order_query['ID']]))
unset($meta[$order_query['ID']]);
$order_ids_skipped[] = $order_query['ID'];
continue;
}
if (in_array($order_query['ID'], $order_ids_skipped)) continue;
if (!isset($csv_data[$order_query['ID']]))
$csv_data[$order_query['ID']] = array(
'order_date' => $order_query['post_date']
);
$meta[$order_query['ID']][$order_query['meta_key']] = $order_query['meta_value'];
if ($order_query['meta_key'] == '_billing_email')
$emails[] = $order_query['meta_value'];
}
}
$uresult->close();
if (!empty($meta))
{
foreach($meta as $order_id => $meta_data)
{
$billing = array(
'addr1' => !empty($meta_data['_billing_address_1']) ? $meta_data['_billing_address_1'] : '',
'addr2' => !empty($meta_data['_billing_address_2']) ? $meta_data['_billing_address_2'] : '',
'city' => !empty($meta_data['_billing_city']) ? $meta_data['_billing_city'] : '',
'state' => !empty($meta_data['_billing_state']) ? $meta_data['_billing_state'] : '',
'zip' => !empty($meta_data['_billing_postcode']) ? $meta_data['_billing_postcode'] : '',
'country' => !empty($meta_data['_billing_country']) ? $meta_data['_billing_country'] : ''
);
$shipping = array(
'addr1' => !empty($meta_data['_shipping_address_1']) ? $meta_data['_shipping_address_1'] : '',
'addr2' => !empty($meta_data['_shipping_address_2']) ? $meta_data['_shipping_address_2'] : '',
'city' => !empty($meta_data['_shipping_city']) ? $meta_data['_shipping_city'] : '',
'state' => !empty($meta_data['_shipping_state']) ? $meta_data['_shipping_state'] : '',
'zip' => !empty($meta_data['_shipping_postcode']) ? $meta_data['_shipping_postcode'] : '',
'country' => !empty($meta_data['_shipping_country']) ? $meta_data['_shipping_country'] : ''
);
$csv_data[$order_id]['name'] = !empty($meta_data['_billing_last_name']) ? trim($meta_data['_billing_first_name']) . ' ' . trim($meta_data['_billing_last_name']) : trim($meta_data['_billing_first_name']);
$csv_data[$order_id]['billing'] = implode(', ', array_filter($billing));
$csv_data[$order_id]['shipping'] = implode(', ', array_filter($shipping));
$csv_data[$order_id]['phone'] = !empty($meta_data['_billing_phone']) ? $meta_data['_billing_phone'] : '';
$csv_data[$order_id]['email'] = !empty($meta_data['_billing_email']) ? $meta_data['_billing_email'] : '';
}
if (!empty($csv_data))
build_csv_file($csv_data, $headers);
}
// No need to continue here.
exit;
function str_putcsv($input, $delimiter = ',', $enclosure = '"')
{
// $fp = fopen('php://temp', 'r+b');
$fp = fopen('php://output', 'r+b');
fputcsv($fp, $input, $delimiter, $enclosure);
rewind($fp);
rtrim(stream_get_contents($fp), "\n");
fclose($fp);
// return $data;
}
function build_csv_file($data, $headers)
{
global $root_dir;
$output = '';
if (empty($data))
return array();
if (!empty($headers))
str_putcsv($headers, ',', '"') . PHP_EOL;
foreach($data as $part)
str_putcsv($part, ',', '"') . PHP_EOL;
}
将此文件保存为testing.php并从wordpress的根目录执行以下url：
https://example.com/testing.php?start=2010-03-05&end=2018-03-05
只返回504网关错误。这绝对是一个PHP内存限制问题，但是，我认为可以流式传输CSV文件，甚至可以在这里使用php://output。不知道如何更好地处理这个问题，以减少正在使用的PHP内存，或者如果有一种方法可以正确地执行此操作，同时仍然正确地维护数据。
有人可以帮我吗？非常感谢。我相信我使用的是PHP 7.2版。你认为这些天php可以更好地处理内存。我相信我的PHP内存最大可达1024MB。我似乎一直在超过PHP内存限制。正在成为一个真正的麻烦。
你在哪里声明变量$ meta
if (isset($meta[$order_query['ID']]))
另外，通过在每个语句块上放置一个调试来知道哪个代码块消耗了那么多内存并且你只能优化那个部分来进行调试是明智的。