Создайте виртуальное окружение [virtual environment](../virtual-environments.md){.internal-link target=_blank}, активируйте его и установите `sqlmodel`:

<div class="termy">

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

</div>

## Создание приложения с единственной моделью

Мы начнем с создания наиболее простой первой версии нашего приложения с одной единственной моделью **SQLModel**.

const noEvictionTTL = time.Hour * 24 * 365 * 10

// because of uint8 usage for nextCleanupBucket, should not exceed 256.
// casting it as uint8 explicitly requires type conversions in multiple places
const numBuckets = 100

// NewLRU returns a new thread-safe cache with expirable entries.
//
// Size parameter set to 0 makes cache of unlimited size, e.g. turns LRU mechanism off.
//
// Providing 0 TTL turns expiring off.
//

    protocol isn't negotiated yet! Previously we'd log HTTP/1.1 by default, and
    this was confusing.
 *  Fix: Omit the message from MockWebServer's HTTP/2 `:status` header.
 *  Fix: Handle 'Expect: 100 Continue' properly in MockWebServer.


## Version 3.8.1

_2017-06-18_

 *  Fix: Recover gracefully from stale coalesced connections. We had a bug where

    void testWriteParametersWireFormatWithOffset() {
        trans2QueryFSInfo = new Trans2QueryFSInformation(config, FileSystemInformation.SMB_INFO_ALLOCATION);

        byte[] buffer = new byte[512];
        int offset = 100;
        int written = trans2QueryFSInfo.writeParametersWireFormat(buffer, offset);

        // Should write 2 bytes at offset
        assertEquals(2, written);

        // Check information level at offset

        trans2SetFileInfo = new Trans2SetFileInformation(config, TEST_FID, mockFileInfo);

        byte[] buffer = new byte[512];
        int offset = 100;
        int written = trans2SetFileInfo.writeDataWireFormat(buffer, offset);

        // Should write FileInformation data + 6 bytes padding
        assertEquals(36, written); // 30 + 6

uvicorn>=0.15.0,<0.16.0
```

Und normalerweise würden Sie diese Paketabhängigkeiten mit `pip` installieren, zum Beispiel:

<div class="termy">

```console
$ pip install -r requirements.txt
---> 100%
Successfully installed fastapi pydantic uvicorn
```

</div>

/// info

Es gibt andere Formate und Tools zum Definieren und Installieren von Paketabhängigkeiten.

    /** Maximum number of retry attempts for failed operations */
    protected int maxRetryCount = 5;

    /** Default number of rows to process in a single batch */
    protected int defaultRowSize = 100;

    /**
     * Default constructor for indexing helper.
     * Creates a new instance with default values.
     */
    public IndexingHelper() {
        // Default constructor
    }

                return 200;
            }
        };
        indexingHelper.setMaxRetryCount(5);
        indexingHelper.setDefaultRowSize(100);
        indexingHelper.setRequestInterval(500);
        ComponentUtil.register(indexingHelper, "indexingHelper");
        ComponentUtil.register(new ThumbnailManager(), "thumbnailManager");

        if (text == null || fromText == null || toText == null) {
            return null;
        }
        final StringBuilder buf = new StringBuilder(100);
        int pos = 0;
        int pos2 = 0;
        while (true) {
            pos = text.indexOf(fromText, pos2);
            if (pos == 0) {
                buf.append(toText);

First, make sure you create your [virtual environment](../virtual-environments.md){.internal-link target=_blank}, activate it, and then install `sqlmodel`:

<div class="termy">

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

</div>

## Create the App with a Single Model { #create-the-app-with-a-single-model }

We'll create the simplest first version of the app with a single **SQLModel** model first.