これを使うことで、デフォルト値を省略して、設定された（リクエストで送られた）データのみを含む`dict`を生成することができます:

```Python hl_lines="34"
{!../../docs_src/body_updates/tutorial002.py!}
```

### Pydanticの`update`パラメータ

ここで、`.copy()`を用いて既存のモデルのコピーを作成し、`update`パラメータに更新するデータを含む`dict`を渡すことができます。

`stored_item_model.copy(update=update_data)`のように:

```Python hl_lines="35"
{!../../docs_src/body_updates/tutorial002.py!}
```

### 部分的更新のまとめ

まとめると、部分的な更新を適用するには、次のようにします:

		switch reflectValue.Kind() {
		case reflect.Slice, reflect.Array:
			var (
				elem        reflect.Value
				isArrayKind = reflectValue.Kind() == reflect.Array
			)

			if !update || reflectValue.Len() == 0 {
				update = false
				if isArrayKind {
					db.Statement.ReflectValue.Set(reflect.Zero(reflectValue.Type()))
				} else {

- If `values.yaml` is changed, be sure to update corresponding values changes in [../profiles/default.yaml](../profiles/default.yaml)

### Step 3. Update istioctl schema

Istioctl uses a [schema](../../operator/pkg/apis/values_types.proto) to validate the values. Any changes to
the schema must be added here, otherwise istioctl users will see errors.
Once the schema file is updated, run:

```bash
$ make operator-proto
```

    }

    @Override
    void compareAndSetSeenExceptions(
        AggregateFutureState<?> state, @CheckForNull Set<Throwable> expect, Set<Throwable> update) {
      seenExceptionsUpdater.compareAndSet(state, expect, update);
    }

    @Override
    int decrementAndGetRemainingCount(AggregateFutureState<?> state) {
      return remainingCountUpdater.decrementAndGet(state);
    }
  }

				return nil
			}
		}
		opts := updateServiceAccountOpts{
			secretKey:     change.Update.SecretKey,
			status:        change.Update.Status,
			name:          change.Update.Name,
			description:   change.Update.Description,
			sessionPolicy: sp,
			expiration:    change.Update.Expiration,
		}

	DB.Model(&hamster).Association("PreferredToy").Find(&hamsterToy)
	if hamsterToy.Name != "bike 2" {
		t.Errorf("Should update has one polymorphic association with Append")
	}

	hamsterToy = Toy{}
	DB.Model(&hamster).Association("OtherToy").Find(&hamsterToy)
	if hamsterToy.Name != "treadmill 2" {
		t.Errorf("Should update has one polymorphic association with Append")
	}

	if DB.Model(&hamster2).Association("PreferredToy").Count() != 1 {

			"SELECT * FROM `users` FOR UPDATE NOWAIT", nil,
		},
		{
			[]clause.Interface{clause.Select{}, clause.From{}, clause.Locking{Strength: clause.LockingStrengthUpdate, Options: clause.LockingOptionsSkipLocked}},
			"SELECT * FROM `users` FOR UPDATE SKIP LOCKED", nil,
		},
	}

	for idx, result := range results {

	if err := DB.Save(&user).Error; err != nil {
		t.Fatalf("errors happened when update: %v", err)
	}

	var user3 User
	DB.Preload("Languages").Preload("Friends").Find(&user3, "id = ?", user.ID)
	CheckUser(t, user2, user3)

	if err := DB.Session(&gorm.Session{FullSaveAssociations: true}).Save(&user).Error; err != nil {
		t.Fatalf("errors happened when update: %v", err)
	}

	var user4 User

   *
   * <p>Changes to the returned map will update the underlying table, and vice versa.
   *
   * @param columnKey key of column to search for in the table
   * @return the corresponding map from row keys to values
   */
  Map<R, V> column(@ParametricNullness C columnKey);

  /**
   * Returns a set of all row key / column key / value triplets. Changes to the returned set will

app = FastAPI()


@app.get("/items/{item_id}")
async def read_item(item_id: str, q: str | None = None, short: bool = False):
    item = {"item_id": item_id}
    if q:
        item.update({"q": q})
    if not short:
        item.update(
            {"description": "This is an amazing item that has a long description"}
        )