if fieldStruct := modelType.Field(i); ast.IsExported(fieldStruct.Name) {
			if field := schema.ParseField(fieldStruct); field.EmbeddedSchema != nil {
				schema.Fields = append(schema.Fields, field.EmbeddedSchema.Fields...)
			} else {
				schema.Fields = append(schema.Fields, field)
			}
		}
	}

	for _, field := range schema.Fields {
		if field.DBName == "" && field.DataType != "" {

      <name>Metadata</name>
      <version>1.0.0+</version>
      <fields>
        <field xml.attribute="true" xml.tagName="modelVersion">
          <name>modelVersion</name>
          <version>1.1.0+</version>
          <type>String</type>
          <description>The version of the underlying metadata model.</description>
        </field>
        <field>
          <name>groupId</name>
          <version>1.0.0+</version>

  // still succeed if there are no other errors, and will only persist
  // the last of any duplicate fields. This is the default in v1.23+
  // - Strict: This will fail the request with a BadRequest error if
  // any unknown fields would be dropped from the object, or if any
  // duplicate fields are present. The error returned from the server
  // will contain all unknown and duplicate fields encountered.

        return getUpdatedAt();
    }

    public void addField(final String key, final Object value) {
        fields.put(key, value);
    }

    @Override
    public Map<String, Object> toSource() {
        final Map<String, Object> sourceMap = super.toSource();
        if (fields != null) {
            sourceMap.putAll(fields);
        }
        return sourceMap;
    }

    @Override

    # fields but it's the same one, so count them by name
    body_param_names_set = {field.name for field in fields}
    # A top level field has to be a single field, not multiple
    if len(body_param_names_set) > 1:
        return True
    first_field = fields[0]
    # If it explicitly specifies it is embedded, it has to be embedded

// GetIdentityFieldValuesMapFromValues get identity map from fields
func GetIdentityFieldValuesMapFromValues(ctx context.Context, values []interface{}, fields []*Field) (map[string][]reflect.Value, [][]interface{}) {
	resultsMap := map[string][]reflect.Value{}
	results := [][]interface{}{}

	for _, v := range values {
		rm, rs := GetIdentityFieldValuesMap(ctx, reflect.Indirect(reflect.ValueOf(v)), fields)
		for k, v := range rm {

The `HeroUpdate` *data model* is somewhat special, it has **all the same fields** that would be needed to create a new hero, but all the fields are **optional** (they all have a default value). This way, when you update a hero, you can send just the fields that you want to update.

Because all the **fields actually change** (the type now includes `None` and they now have a default value of `None`), we need to **re-declare** them.

                if (q instanceof BooleanQuery) {
                    queryList.addAll(getTermQueryList(q, fields));
                } else if (q instanceof final TermQuery termQuery) {
                    for (final String field : fields) {
                        if (field.equals(termQuery.getTerm().field())) {
                            queryList.add(termQuery);
                        }
                    }

      <description>Dependency collection or resolution injection.</description>
      <fields>
        <field>
          <name>field</name>
          <required>false</required>
          <version>2.0.0+</version>
          <type>String</type>
          <description>the name of the field to be injected</description>
        </field>
        <field>
          <name>pathScope</name>
          <required>false</required>

/// note

This is supported since FastAPI version `0.114.0`. 🤓

///

You can use Pydantic's model configuration to `forbid` any `extra` fields:

//// tab | Python 3.9+

```Python hl_lines="12"
{!> ../../docs_src/request_form_models/tutorial002_an_py39.py!}
```

////

//// tab | Python 3.8+

```Python hl_lines="11"