33岁孕妈经历4天分娩 宝宝出生时张开双臂迎接世界

百度 我想，可能是秋老师觉得自己并不是明星艺人，知名度不高，所以就想多做一些，赢得点好感！不过，各位明星艺人们倒是做的不是很对了，似乎是将秋老师所做的种种当成了理所应当，于是就有了下面这样的事情发生！有一次，李静带着一群人出去玩了，并且交代秋老师，6点钟回来要准时开饭！秋老师也一口答应了，但是下午呢，秋老师看着时间还早，与何穗一起将工作做完了，就和游客一起出去爬山了！在这期间，李静还打电话回来顶住秋老师一定要准备好饭菜，是程晓玥接的电话，她明明知道秋老师不再，但还是一口答应了下来，搞不懂这是什么逻辑！等到李静等人回来的时候，见到秋老师不再，瞬间李静就炸了，非常生气的样子！等到秋老师回来之后，发现自己玩的太高兴，忘记了时间，也是一脸的愧疚！秋老师道歉的态度也是非常的诚恳，先是和戴军老师道歉，随后又和何穗道歉，态度也是相当的诚恳，但却被何穗一脸不耐烦的推开了！最后，秋老师去给李静道歉，整个过程，李静都没有给秋老师任何的好脸色，最终还是别的人家给秋老师求情，李静才勉为其难的原谅了秋老师！其实，我很不懂，为什么秋老师要为大家道歉，本来做饭就不是一个人的事情啊！我想，很多看过节目的人都会很气愤，明星艺人就可以高人一等的对素人秋老师颐指气使了么？可能真的是因为秋老师是一个素人吧！不出意外的是，在节目播出之后，李静自然是成为了网友群起攻之的对象，而何穗也没有被网友拉下！依照何穗的微博，我能想到的只有这件事了，毕竟那时候何穗也是被人指责过于势力了！但综艺节目么，不要天当真了，通过后期剪辑，可以制造出各种各样的效果，如今旧事被重提，看来何穗真的是被冤枉了！秋老师在微博中也为何穗辩解过，还称赞何穗是非常会照顾人的知心大姐姐，但不晓得何穗为什么不自己去澄清，反而是要背负这这样的骂名！所以，对待综艺节目，我们要辩证的去看待，毕竟为了收视率，后期是什么都能做的出来的！本文来自凤凰号，仅代表凤凰号自媒体观点。

Avoid N 1 query problems, reduce the number of database queries by loading associated data in advance; 2. Select only the required fields to avoid loading complete entities to save memory and bandwidth; 3. Use cache strategies reasonably, such as Doctrine's secondary cache or Redis cache high-frequency query results; 4. Optimize the entity life cycle and call clear() regularly to free up memory to prevent memory overflow; 5. Ensure that the database index exists and analyze the generated SQL statements to avoid inefficient queries; 6. Disable automatic change tracking in scenarios where changes are not required, and use arrays or lightweight modes to improve performance. Correct use of ORM requires combining SQL monitoring, caching, batch processing and appropriate optimization to ensure application performance while maintaining development efficiency.

Object-Relational Mapping (ORM) tools like Doctrine, Eloquent (Laravel), and Propel make PHP development faster and more maintainable by letting you work with databases using object-oriented code. But they come with a performance cost if used carefully. Poorly tuned ORM usage can lead to slow queries, memory bloat, and scalability issues — especially under load.

Here's how to keep your ORM performant without giving up its productivity benefits.

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1. Avoid the N 1 Query Problem

This is the most common ORM performance killer.

When you fetch a list of objects and access a related entity inside a loop, ORMs often issue one additional query per object — leading to N 1 queries.

Example (bad):

 $users = $entityManager->getRepository(User::class)->findAll();
foreach ($users as $user) {
    echo $user->getProfile()->getEmail(); // One extra query per user
}

If you have 100 users, this results in 101 queries.

Fix: Use Eager Loading

Load related data up front using joins.

• Doctrine: Use JOIN FETCH in DQL or configure fetch mode in associations.

   $dql = "SELECT u, p FROM User u JOIN FETCH u.profile p";
  $users = $entityManager->createQuery($dql)->getResult();

• Eloquent: Use with() to eager load relationships.

   $users = User::with('profile')->get();
  foreach ($users as $user) {
      echo $user->profile->email;
  }

Always monitor your logs or use tools like Laravel Debugbar or Doctrine's SQL logger to catch N 1 issues early.

---

2. Select Only What You Need

Fetching entire entities when you only need a few fields wastes memory and bandwidth.

Instead of:

 $users = $repo->findAll();
foreach ($users as $user) {
    echo $user->getName();
}

Use partial or scalar queries:

• Doctrine: Use DQL to select specific fields.

   $dql = "SELECT u.id, u.name FROM User u";
  $users = $entityManager->createQuery($dql)->getScalarResult();

• Eloquent: Use select() and pluck() / get() .

   $names = User::select('id', 'name')->get();

For read-only operations, consider using raw queries or DTOs (Data Transfer Objects) via custom SQL — you'll get much better performance.

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3. Leverage Caching Strategically

ORMs work best when combined with proper caching layers.

• Second-Level Cache (Doctrine): Cache entire entities or collections.

   // In Doctrine
  $query->useResultCache(true, 3600, 'users_list');

• Query Cache: Store the results of DQL parsing and SQL generation.

• Redis/Memcached Eloquent: Cache frequently queries.

   $users = Cache::remember('users.active', 3600, function () {
      return User::where('active', 1)->get();
  });

Be careful with cache invalidation, but even short TTLs on high-read endpoints can drastically reduce DB load.

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4. Optimize Entity Lifecycle and Memory Usage

ORMs track object state, which consumes memory. Long-running scripts (eg, imports, batch jobs) can run out of memory.

Problem:

 for ($i = 0; $i < 10000; $i ) {
    $user = new User();
    $user->setName("User $i");
    $entityManager->persist($user);
}
$entityManager->flush();

All 10k entities are tracked in memory.

Fix: Use clear() or detach() periodically

 for ($i = 0; $i < 10000; $i ) {
    $user = new User();
    $user->setName("User $i");
    $entityManager->persist($user);

    if ($i % 1000 === 0) {
        $entityManager->flush();
        $entityManager->clear(); // Free memory
    }
}

This keeps memory usage constant regardless of dataset size.

---

5. Use Indexes and Analyze Queries

Even the best ORM code can't fix missing database indexes.

• Always index foreign keys and frequently queried columns.
• Use EXPLAIN on generated SQL to spot full table scans.
• Monitor slow query logs.

Example: If you often query User WHERE status = ? , make sure status is indexed.

Also, avoid complex ORM queries that generate inefficient SQL. Sometimes, writing a hand-optimized query is better than forcing the ORM to do it.

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6. Disable Auto-Change Tracking When Not Needed

In read-heavy operations, you don't need the ORM to track changes.

• Doctrine: Use HYDRATE_ARRAY or detach entities.

   $users = $entityManager->createQuery($dql)
      ->setHydrationMode(Query::HYDRATE_ARRAY)
      ->getResult();

  Arrays are faster and lighter than full entities.

  • In Eloquent, use toArray() early or use select() with get() to avoid model overhead.

  ---

  Final Thoughts

  ORMs are powerful — but they're not magic. Performance tuning means:

  • Knowing when to step around them
  • Understanding what SQL they generate
  • Using tools to detect problems (N 1, memory leaks)
  • Applying caching and batching where appropriate

  You don't have to abandon ORM to go fast. Just use it wisely.

  Basically: fetch less, cache more, and always check the SQL .

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