Method fields

ormar/queryset/queryset.py:532–590

With `fields()` you can select subset of model columns to limit the data load. Note that `fields()` and `exclude_fields()` works both for main models (on normal queries like `get`, `all` etc.) as well as `select_related` and `prefetch_related` models (with n

(
        self, columns: Union[list, str, set, dict], slot: "Slot" = "include"
    )

        return select_paths, prefetch_paths

    def fields(
        self, columns: Union[list, str, set, dict], slot: "Slot" = "include"
    ) -> "QuerySet[T]":
        """
        With `fields()` you can select subset of model columns to limit the data load.

        Note that `fields()` and `exclude_fields()` works both for main models
        (on normal queries like `get`, `all` etc.)
        as well as `select_related` and `prefetch_related`
        models (with nested notation).

        You can select specified fields by passing a `str, list[str], set[str] or
        dict` with nested definition.

        To include related models use notation
        `{related_name}__{column}[__{optional_next} etc.]`.

        `fields()` can be called several times, building up the columns to select.

        If you include related models into `select_related()` call but you won't specify
        columns for those models in fields - implies a list of all fields for
        those nested models.

        Mandatory fields cannot be excluded as it will raise `ValidationError`,
        to exclude a field it has to be nullable.

        Pk column cannot be excluded - it's always auto added even if
        not explicitly included.

        You can also pass fields to include as dictionary or set.

        To mark a field as included in a dictionary use it's name as key
        and ellipsis as value.

        To traverse nested models use nested dictionaries.

        To include fields at last level instead of nested dictionary a set can be used.

        To include whole nested model specify model related field name and ellipsis.

        :param slot: which Excludable slot to write into ("include" or "exclude")
        :type slot: Slot
        :param columns: columns to include
        :type columns: Union[list, str, set, dict]
        :return: QuerySet
        :rtype: QuerySet
        """
        excludable = ormar.ExcludableItems.from_excludable(self._excludable)
        excludable.build(
            items=columns,
            model_cls=self.model_cls,  # type: ignore
            slot=slot,
        )
        if excludable._flatten_paths:
            excludable.validate_flatten_vs_excludable(
                source_model=self.model_cls  # type: ignore
            )