Есть несколько отличий:

* `table=True` сообщает SQLModel, что это *модель-таблица*, она должна представлять **таблицу** в SQL базе данных, это не просто *модель данных* (как обычный класс Pydantic).

* `Field(primary_key=True)` сообщает SQLModel, что `id` — это **первичный ключ** в SQL базе данных (подробнее о первичных ключах SQL можно узнать в документации SQLModel).

```

……因为路径中没有必选参数 `needy`，返回的响应中会显示如下错误信息：

```JSON
{
    "detail": [
        {
            "loc": [
                "query",
                "needy"
            ],
            "msg": "field required",
            "type": "value_error.missing"
        }
    ]
}
```

`needy` 是必选参数，因此要在 URL 中设置值：

```
http://127.0.0.1:8000/items/foo-item?needy=sooooneedy
```

……这样就正常了：

		parsedURL, err := url.ParseRequestURI(req.RequestURI)
		if err == nil {
			u = parsedURL
		}
	}
	return u
}

// copyURL provides update safe copy by avoiding shallow copying User field
func copyURL(i *url.URL) *url.URL {
	out := *i
	if i.User != nil {
		u := *i.User
		out.User = &u
	}
	return &out
}

// Modify the request to handle the target URL

                        "uses the unsupported value 'legacy', artifact resolution might fail.");
            }
        }
    }

    // ----------------------------------------------------------------------
    // Field validation
    // ----------------------------------------------------------------------

    /**
     * Asserts:
     * <p/>
     * <ul>
     * <li><code>string.length != null</code>

      metadata.is_list = 1;
      metadata.list_size = 0;
      metadata.total_size = -1;
#define LIST_CASE(field, attr_type, ...)              \
  if (attr->list().field##_size() > 0) {              \
    metadata.type = attr_type;                        \
    metadata.list_size = attr->list().field##_size(); \
    __VA_ARGS__;                                      \
    break;                                            \

     * <code>SystemStreamLog</code> logger will be created and returned.
     * </p>
     * <strong>Note:</strong>
     * The logger returned by this method must not be cached in an instance field during the construction of the mojo.
     * This would cause the mojo to use a wrongly configured default logger when being run by Maven. The proper logger

///

## Anotaciones de tipos con metadata { #type-hints-with-metadata-annotations }

1. This is the generator function. It's a "generator function" because it contains `yield` statements inside.
2. By using a `with` block, we make sure that the file-like object is closed after the generator function is done. So, after it finishes sending the response.
3. This `yield from` tells the function to iterate over that thing named `file_like`. And then, for each part iterated, yield that part as coming from this generator function (`iterfile`).

  fmt.Printf("%v\n ", mv.Value)
}
```

output:
```
map[desc:RGB colors:[red green blue]]
map[desc:CMYK colors:[cyan magenta yellow black]]
```

likewise, increasing depth level to `3` yields:
```
red
green
blue
cyan
magenta
yellow
black
```

optionally, kev:value pairs can be emitted as an individual struct:
```go

	if !strings.HasPrefix(hostAddr, "http://") && !strings.HasPrefix(hostAddr, "https://") {
		hostAddr = "//" + hostAddr
	}

	// Parse address to extract host and scheme field
	u, err := url.Parse(hostAddr)
	if err != nil {
		return "", "", err
	}

	addr = u.Host
	scheme = u.Scheme

	// Use the given parameter again if url.Parse()
	// didn't return any useful result.