*
 * <p>This implementation is based on the <a
 * href="http://portal.acm.org/citation.cfm?id=6621">min-max heap</a> developed by Atkinson, et al.
 * Unlike many other double-ended priority queues, it stores elements in a single array, as compact
 * as the traditional heap data structure used in {@link PriorityQueue}.
 *
 * <p>This class is not thread-safe, and does not accept null elements.
 *
 * <p><i>Performance notes:</i>
 *
 * <ul>

    Monitor monitor = this.monitor;
    monitor.enter();
    try {
      return items.length - count;
    } finally {
      monitor.leave();
    }
  }

  /**
   * Removes a single instance of the specified element from this queue, if it is present. More
   * formally, removes an element {@code e} such that {@code o.equals(e)}, if this queue contains

首先，請先建立你的[虛擬環境](../virtual-environments.md)、啟用它，然後安裝 `sqlmodel`：

<div class="termy">

```console
$ pip install sqlmodel
---> 100%
```

</div>

## 建立只有單一模型的應用 { #create-the-app-with-a-single-model }

我們先用單一 SQLModel 模型建立這個應用的最簡版。

接著我們會在下方用多個模型來提升安全性與彈性。🤓

### 建立模型 { #create-models }

匯入 `SQLModel` 並建立一個資料庫模型：

{* ../../docs_src/sql_databases/tutorial001_an_py310.py ln[1:11] hl[7:11] *}

  //
  // class Entry {
  //    int hash;
  //    Entry next;
  //    K key;
  //    V value;
  // }
  //
  // The imaginary `hash` and `next` values are combined into a single `int` value in the `entries`
  // array. The top bits of this value are the remaining bits of the hash value that were not used
  // in the short hash. We saw that a mask of 0x7f would keep the 7-bit value 0x6f from a full

まずは [仮想環境](../virtual-environments.md) を作成・有効化し、`sqlmodel` をインストールします:

<div class="termy">

```console
$ pip install sqlmodel
---> 100%
```

</div>

## 単一モデルでアプリ作成 { #create-the-app-with-a-single-model }

まずは最も簡単な、単一の SQLModel モデルだけを使うバージョンを作ります。

後で、下記のとおり複数モデルにしてセキュリティと汎用性を高めます。🤓

### モデルの作成 { #create-models }

`SQLModel` をインポートしてデータベースモデルを作成します:

injection system requires pre-registration of the dependencies and the dependencies are solved based on the declared types. So, it's not possible to declare more than one "component" that provides a certain type.

Routes are declared in a single place, using functions declared in other places (instead of using decorators that can be placed right on top of the function that handles the endpoint). This is closer to how Django does it than to how Flask (and Starlette) does it. It separates in...

Just standard **Python**.

For example, for an `int`:

```Python
item_id: int
```

or for a more complex `Item` model:

```Python
item: Item
```

...and with that single declaration you get:

* Editor support, including:
    * Completion.
    * Type checks.
* Validation of data:
    * Automatic and clear errors when the data is invalid.

				if filterLifecycle(bucket, version.Name, version) {
					expired++
					stopFn(version.Size, errors.New("ILM expired object/version will be skipped"))
					continue
				}

				// any object with only single DEL marker we don't need
				// to rebalance, just skip it, this also includes
				// any other versions that have already expired.
				remainingVersions := len(fivs.Versions) - expired

   *
   * <p>This must be a (2^n)-1 as it is used as a mask.
   */
  static final int DRAIN_THRESHOLD = 0x3F;

  /**
   * Maximum number of entries to be drained in a single cleanup run. This applies independently to
   * the cleanup queue and both reference queues.
   */
  // TODO(fry): empirically optimize this
  static final int DRAIN_MAX = 16;

  // Fields

  /**

    // The soft hyphen (­) should be ignored.
    assertThat(parse("http://AB\u00adCD").host).isEqualTo("abcd")
  }

  @Test
  fun hostnameMultipleCharacterMapping() {
    // Map the single character telephone symbol (℡) to the string "tel".
    assertThat(parse("http://\u2121").host).isEqualTo("tel")
  }

  @Test
  fun hostnameMappingLastMappedCodePoint() {