1. The industry news page cache was not updating in time. When a new article was added in the backend, the frontend list page did not update immediately; it always took a 5-minute wait before updating, making it seem like the page cache dependency was not taking effect. The two latest articles in the backend were not synced to the frontend for update. See Figure 1.
2. However, the same program works normally in the local environment. Upon closer analysis of the differences, I found that the article update time in the production environment’s backend was 8 hours earlier than Beijing Time. If updated_at stores UTC time (which is 8 hours behind Beijing Time) and you use Beijing Time for the check (for example, when seeing that the page hasn’t updated), the following occurs:
The data has actually been updated (Beijing Time 15:30),
but updated_at is 2025-06-05 07:30:25 (UTC),
so the MAX(updated_at) that the cache check relies on hasn’t changed, and the page continues to use the old cache.
public function behaviors()
{
$request = Yii::$app->request;
$alias = $request->get('alias');
$id = $request->get('id');
$categoryId = (int)$request->get('c', 0);
$keyword = trim($request->get('k'));
$tag = $request->get('tag');
$page = (int)$request->get('page', 1);
$detect = new MobileDetect();
$isMobile = $detect->isMobile() ? PageElementType::DEVICE_TYPE_MOBILE : PageElementType::DEVICE_TYPE_PC;
$behaviors = [];
// view 页面缓存
if (!empty($alias)) {
$dependency = new DbDependency([
'sql' => 'SELECT updated_at FROM articles WHERE alias = :alias LIMIT 1',
'params' => [':alias' => $alias],
]);
} elseif (!empty($id)) {
$dependency = new DbDependency([
'sql' => 'SELECT updated_at FROM articles WHERE id = :id LIMIT 1',
'params' => [':id' => $id],
]);
} else {
$dependency = null;
}
$behaviors['pageCacheView'] = [
'class' => PageCache::class,
'only' => ['view'],
'duration' => 300,
'variations' => [$id, $alias, $isMobile],
'dependency' => $dependency,
'cache' => 'fileCache',
];
// index 页面缓存，仅当无关键词和标签时启用
if ($keyword === '' && empty($tag)) {
$category = null;
if (!empty($alias) && UrlHelper::isValidAlias($alias)) {
$category = Yii::$app->db->cache(fn() => ArticleCategory::find()
->where(['alias' => $alias, 'status' => CommonArticleCategory::STATUS_NORMAL])
->limit(1)
->one(), 300);
} elseif (!empty($categoryId)) {
$category = Yii::$app->db->cache(fn() => ArticleCategory::find()
->where(['id' => $categoryId, 'status' => CommonArticleCategory::STATUS_NORMAL])
->limit(1)
->one(), 300);
}
if ($category !== null) {
// 有分类筛选，仅依赖该分类的文章更新时间
$indexDependency = new DbDependency([
'sql' => 'SELECT MAX(updated_at) FROM articles WHERE status = 1 AND category_id = :categoryId',
'params' => [':categoryId' => $category->id],
]);
} else {
// 无分类筛选，才依赖全表（不建议再进一步切分，否则复杂度会上升）
$indexDependency = new DbDependency([
'sql' => 'SELECT MAX(updated_at) FROM articles WHERE status = 1',
]);
}
$behaviors['pageCacheIndex'] = [
'class' => PageCache::class,
'only' => ['index'],
'duration' => 300,
'variations' => [
$categoryId,
$alias,
$page,
$isMobile,
],
'dependency' => $indexDependency,
'cache' => 'fileCache',
];
}
return $behaviors;
}
3. I checked the timezone setting in php.ini, which is equivalent to date.timezone = Asia/Shanghai. I decided to change it to date.timezone = Asia/Shanghai.
date.timezone = PRC
4. Set the MySQL connection timezone to ensure that your PHP database connection uses the +08:00 timezone. In Yii2, you can do this as follows:
'components' => [
'db' => [
// ... 其他配置
'on afterOpen' => function($event) {
$event->sender->createCommand("SET time_zone = '+08:00'")->execute();
},
],
],
5. After editing an article, its update time is now in the Beijing timezone. See Figure 2.
