Struct arrow_array::array::MapArray

pub struct MapArray { /* private fields */ }

A nested array type where each record is a key-value map. Keys should always be non-null, but values can be null.

MapArray is physically a crate::array::ListArray that has a StructArray with 2 child fields.

Implementations

impl MapArray

pub fn keys(&self) -> &ArrayRef

Returns a reference to the keys of this map.

pub fn values(&self) -> &ArrayRef

Returns a reference to the values of this map.

pub fn key_type(&self) -> &DataType

Returns the data type of the map’s keys.

pub fn value_type(&self) -> &DataType

Returns the data type of the map’s values.

pub unsafe fn value_unchecked(&self, i: usize) -> ArrayRef

Returns ith value of this map array.

This is a StructArray containing two fields

Safety

Caller must ensure that the index is within the array bounds

pub fn value(&self, i: usize) -> ArrayRef

Returns ith value of this map array.

This is a StructArray containing two fields

pub fn value_offsets(&self) -> &[i32]

Returns the offset values in the offsets buffer

pub fn value_length(&self, i: usize) -> i32

Returns the length for value at index i.

impl MapArray

pub fn new_from_strings<'a>( keys: impl Iterator<Item = &'a str>, values: &dyn Array, entry_offsets: &[u32] ) -> Result<Self, ArrowError>

Creates map array from provided keys, values and entry_offsets.

Trait Implementations

impl Array for MapArray

fn get_buffer_memory_size(&self) -> usize

Returns the total number of bytes of memory occupied by the buffers owned by this MapArray.

fn get_array_memory_size(&self) -> usize

Returns the total number of bytes of memory occupied physically by this MapArray.

fn as_any(&self) -> &dyn Any

Returns the array as Any so that it can be downcasted to a specific implementation.

fn data(&self) -> &ArrayData

Returns a reference to the underlying data of this array.

fn into_data(self) -> ArrayData

Returns the underlying data of this array.

fn data_ref(&self) -> &ArrayData

Returns a reference-counted pointer to the underlying data of this array.

fn data_type(&self) -> &DataType

Returns a reference to the DataType of this array.

fn slice(&self, offset: usize, length: usize) -> ArrayRef

Returns a zero-copy slice of this array with the indicated offset and length.

fn len(&self) -> usize

Returns the length (i.e., number of elements) of this array.

fn is_empty(&self) -> bool

Returns whether this array is empty.

fn offset(&self) -> usize

Returns the offset into the underlying data used by this array(-slice). Note that the underlying data can be shared by many arrays. This defaults to 0.

fn is_null(&self, index: usize) -> bool

Returns whether the element at index is null. When using this function on a slice, the index is relative to the slice.

fn is_valid(&self, index: usize) -> bool

Returns whether the element at index is not null. When using this function on a slice, the index is relative to the slice.

fn null_count(&self) -> usize

Returns the total number of null values in this array.

impl Clone for MapArray

fn clone(&self) -> MapArray

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for MapArray

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl From<ArrayData> for MapArray

fn from(data: ArrayData) -> Self

Converts to this type from the input type.

impl From<MapArray> for ArrayData

fn from(array: MapArray) -> Self

Converts to this type from the input type.

impl PartialEq<MapArray> for MapArray

fn eq(&self, other: &Self) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.