Enum datafusion_expr::field_util::GetFieldAccessSchema

pub enum GetFieldAccessSchema {
    NamedStructField {
        name: ScalarValue,
    },
    ListIndex {
        key_dt: DataType,
    },
    ListRange {
        start_dt: DataType,
        stop_dt: DataType,
    },
}

Types of the field access expression of a nested type, such as Field or List

Variants

NamedStructField

Fields

name: ScalarValue

Named field, For example struct["name"]

ListIndex

Fields

key_dt: DataType

Single list index, for example: list[i]

ListRange

Fields

start_dt: DataType

stop_dt: DataType

List range, for example list[i:j]

Implementations

impl GetFieldAccessSchema

pub fn get_accessed_field(&self, data_type: &DataType) -> Result<Field>

Returns the schema [Field] from a [DataType::List] or [DataType::Struct] indexed by this structure

Error

Errors if

• the data_type is not a Struct or a List,
• the data_type of the name/index/start-stop do not match a supported index type