**`Session`** хранит **объекты в памяти** и отслеживает необходимые изменения в данных, затем **использует `engine`** для общения с базой данных.

Мы создадим **зависимость** FastAPI с `yield`, которая будет предоставлять новую `Session` для каждого запроса. Это и обеспечивает использование одной сессии на запрос. 🤓

  void awaitTimedWaiting(Thread thread) {
    while (true) {
      switch (thread.getState()) {
        case BLOCKED:
        case NEW:
        case RUNNABLE:
        case WAITING:
          Thread.yield();
          break;
        case TIMED_WAITING:
          return;
        case TERMINATED:
          throw new AssertionError();
      }
    }
  }

Wir werden eine FastAPI **Abhängigkeit** mit `yield` erstellen, die eine neue `Session` für jeden Request bereitstellt. Das ist es, was sicherstellt, dass wir eine einzige Session pro Request verwenden. 🤓

Crearemos una **dependencia de FastAPI** con `yield` que proporcionará una nueva `Session` para cada request. Esto es lo que asegura que usemos una sola session por request. 🤓

    void awaitWaiting() {
      while (!isBlocked()) {
        if (getState() == State.TERMINATED) {
          throw new RuntimeException("Thread exited");
        }
        Thread.yield();
      }
    }

    private boolean isBlocked() {
      return getState() == Thread.State.WAITING && LockSupport.getBlocker(this) == future;
    }
  }

Une **`Session`** est ce qui stocke les **objets en mémoire** et suit les modifications nécessaires des données, puis **utilise l'`engine`** pour communiquer avec la base.

Nous allons créer une **dépendance** FastAPI avec `yield` qui fournira une nouvelle `Session` pour chaque requête. C'est ce qui garantit que nous utilisons une seule session par requête. 🤓

              });
      expectedKeys.add(s);
    }

    computationLatch.countDown();
    // let some computations complete
    while (computedCount.get() < nThreads) {
      Thread.yield();
    }
    cache.invalidateAll();
    tasksFinished.await();

    // Check all of the removal notifications we received: they should have had correctly-associated

              });
      expectedKeys.add(s);
    }

    computationLatch.countDown();
    // let some computations complete
    while (computedCount.get() < nThreads) {
      Thread.yield();
    }
    cache.invalidateAll();
    tasksFinished.await();

    // Check all of the removal notifications we received: they should have had correctly-associated

{* ../../docs_src/sql_databases/tutorial001_an_py310.py ln[21:22] hl[21:22] *}

### 세션 의존성 생성하기 { #create-a-session-dependency }

**`Session`**은 **메모리에 객체**를 저장하고 데이터에 필요한 모든 변경 사항을 추적한 후, **`engine`을 통해** 데이터베이스와 통신합니다.

`yield`를 사용해 FastAPI의 **의존성**을 생성하여 각 요청마다 새로운 `Session`을 제공합니다. 이는 요청당 하나의 세션만 사용되도록 보장합니다. 🤓

그런 다음 이 의존성을 사용하는 나머지 코드를 간소화하기 위해 `Annotated` 의존성 `SessionDep`을 생성합니다.

    *   Mutable tables now restore checkpointed values when loaded from
        SavedModel.
    *   The user object metadata field in the SavedModel proto has been
        deprecated as part of the updates to Keras SavedModel. Keras was the
        only consumer of this field prior to the update.
*   GPU
    *   TF 2.3 includes PTX kernels only for
        [compute capability](https://developer.nvidia.com/cuda-gpus) 7.0 to