Struct Dictionary 

pub struct Dictionary<K, V>(/* private fields */);

Wrapper denoting an Arrow Dictionary column with key type K and values of V.

The inner value is intentionally not exposed. Construct with Dictionary::new and access the contained value via Dictionary::value or Dictionary::into_value.

This prevents accidental reliance on representation details (e.g., raw keys) and keeps the API focused on appending logical values. The builder handles interning to keys.

Implementations

impl<K, V> Dictionary<K, V>

pub fn new(value: V) -> Self

Create a new dictionary value wrapper.

pub fn value(&self) -> &V

Borrow the contained logical value.

pub fn into_value(self) -> V

Consume and return the contained logical value.

Trait Implementations

impl<K, const N: usize> ArrowBinding for Dictionary<K, [u8; N]>

where K: DictKey, <K as DictKey>::ArrowKey: ArrowDictionaryKeyType,

type Builder = FixedSizeBinaryDictionaryBuilder<<K as DictKey>::ArrowKey>

Concrete Arrow builder type used for this Rust type.

type Array = DictionaryArray<<K as DictKey>::ArrowKey>

Concrete Arrow array type produced by finish.

fn data_type() -> DataType

The Arrow DataType corresponding to this Rust type.

fn new_builder(_capacity: usize) -> Self::Builder

Create a new builder with an optional capacity hint.

fn append_value(b: &mut Self::Builder, v: &Self)

Append a non-null value to the builder.

fn append_null(b: &mut Self::Builder)

Append a null to the builder.

fn finish(b: Self::Builder) -> Self::Array

Finish the builder and produce a typed Arrow array.

impl<K> ArrowBinding for Dictionary<K, LargeBinary>

where K: DictKey, <K as DictKey>::ArrowKey: ArrowDictionaryKeyType,

type Builder = GenericByteDictionaryBuilder<<K as DictKey>::ArrowKey, GenericBinaryType<i64>>

Concrete Arrow builder type used for this Rust type.

type Array = DictionaryArray<<K as DictKey>::ArrowKey>

Concrete Arrow array type produced by finish.

fn data_type() -> DataType

The Arrow DataType corresponding to this Rust type.

fn new_builder(_capacity: usize) -> Self::Builder

Create a new builder with an optional capacity hint.

fn append_value(b: &mut Self::Builder, v: &Self)

Append a non-null value to the builder.

fn append_null(b: &mut Self::Builder)

Append a null to the builder.

fn finish(b: Self::Builder) -> Self::Array

Finish the builder and produce a typed Arrow array.

impl<K> ArrowBinding for Dictionary<K, LargeUtf8>

where K: DictKey, <K as DictKey>::ArrowKey: ArrowDictionaryKeyType,

type Builder = GenericByteDictionaryBuilder<<K as DictKey>::ArrowKey, GenericStringType<i64>>

Concrete Arrow builder type used for this Rust type.

type Array = DictionaryArray<<K as DictKey>::ArrowKey>

Concrete Arrow array type produced by finish.

fn data_type() -> DataType

The Arrow DataType corresponding to this Rust type.

fn new_builder(_capacity: usize) -> Self::Builder

Create a new builder with an optional capacity hint.

fn append_value(b: &mut Self::Builder, v: &Self)

Append a non-null value to the builder.

fn append_null(b: &mut Self::Builder)

Append a null to the builder.

fn finish(b: Self::Builder) -> Self::Array

Finish the builder and produce a typed Arrow array.

impl<K> ArrowBinding for Dictionary<K, String>

where K: DictKey, <K as DictKey>::ArrowKey: ArrowDictionaryKeyType,

type Builder = GenericByteDictionaryBuilder<<K as DictKey>::ArrowKey, GenericStringType<i32>>

Concrete Arrow builder type used for this Rust type.

type Array = DictionaryArray<<K as DictKey>::ArrowKey>

Concrete Arrow array type produced by finish.

fn data_type() -> DataType

The Arrow DataType corresponding to this Rust type.

fn new_builder(_capacity: usize) -> Self::Builder

Create a new builder with an optional capacity hint.

fn append_value(b: &mut Self::Builder, v: &Self)

Append a non-null value to the builder.

fn append_null(b: &mut Self::Builder)

Append a null to the builder.

fn finish(b: Self::Builder) -> Self::Array

Finish the builder and produce a typed Arrow array.

impl<K> ArrowBinding for Dictionary<K, Vec<u8>>

where K: DictKey, <K as DictKey>::ArrowKey: ArrowDictionaryKeyType,

type Builder = GenericByteDictionaryBuilder<<K as DictKey>::ArrowKey, GenericBinaryType<i32>>

Concrete Arrow builder type used for this Rust type.

type Array = DictionaryArray<<K as DictKey>::ArrowKey>

Concrete Arrow array type produced by finish.

fn data_type() -> DataType

The Arrow DataType corresponding to this Rust type.

fn new_builder(_capacity: usize) -> Self::Builder

Create a new builder with an optional capacity hint.

fn append_value(b: &mut Self::Builder, v: &Self)

Append a non-null value to the builder.

fn append_null(b: &mut Self::Builder)

Append a null to the builder.

fn finish(b: Self::Builder) -> Self::Array

Finish the builder and produce a typed Arrow array.

impl<K> ArrowBinding for Dictionary<K, f32>

where K: DictKey, <K as DictKey>::ArrowKey: ArrowDictionaryKeyType,

type Builder = PrimitiveDictionaryBuilder<<K as DictKey>::ArrowKey, Float32Type>

Concrete Arrow builder type used for this Rust type.

type Array = DictionaryArray<<K as DictKey>::ArrowKey>

Concrete Arrow array type produced by finish.

fn data_type() -> DataType

The Arrow DataType corresponding to this Rust type.

fn new_builder(_capacity: usize) -> Self::Builder

Create a new builder with an optional capacity hint.

fn append_value(b: &mut Self::Builder, v: &Self)

Append a non-null value to the builder.

fn append_null(b: &mut Self::Builder)

Append a null to the builder.

fn finish(b: Self::Builder) -> Self::Array

Finish the builder and produce a typed Arrow array.

impl<K> ArrowBinding for Dictionary<K, f64>

where K: DictKey, <K as DictKey>::ArrowKey: ArrowDictionaryKeyType,

type Builder = PrimitiveDictionaryBuilder<<K as DictKey>::ArrowKey, Float64Type>

Concrete Arrow builder type used for this Rust type.

type Array = DictionaryArray<<K as DictKey>::ArrowKey>

Concrete Arrow array type produced by finish.

fn data_type() -> DataType

The Arrow DataType corresponding to this Rust type.

fn new_builder(_capacity: usize) -> Self::Builder

Create a new builder with an optional capacity hint.

fn append_value(b: &mut Self::Builder, v: &Self)

Append a non-null value to the builder.

fn append_null(b: &mut Self::Builder)

Append a null to the builder.

fn finish(b: Self::Builder) -> Self::Array

Finish the builder and produce a typed Arrow array.

impl<K> ArrowBinding for Dictionary<K, i16>

where K: DictKey, <K as DictKey>::ArrowKey: ArrowDictionaryKeyType,

type Builder = PrimitiveDictionaryBuilder<<K as DictKey>::ArrowKey, Int16Type>

Concrete Arrow builder type used for this Rust type.

type Array = DictionaryArray<<K as DictKey>::ArrowKey>

Concrete Arrow array type produced by finish.

fn data_type() -> DataType

The Arrow DataType corresponding to this Rust type.

fn new_builder(_capacity: usize) -> Self::Builder

Create a new builder with an optional capacity hint.

fn append_value(b: &mut Self::Builder, v: &Self)

Append a non-null value to the builder.

fn append_null(b: &mut Self::Builder)

Append a null to the builder.

fn finish(b: Self::Builder) -> Self::Array

Finish the builder and produce a typed Arrow array.

impl<K> ArrowBinding for Dictionary<K, i32>

where K: DictKey, <K as DictKey>::ArrowKey: ArrowDictionaryKeyType,

type Builder = PrimitiveDictionaryBuilder<<K as DictKey>::ArrowKey, Int32Type>

Concrete Arrow builder type used for this Rust type.

type Array = DictionaryArray<<K as DictKey>::ArrowKey>

Concrete Arrow array type produced by finish.

fn data_type() -> DataType

The Arrow DataType corresponding to this Rust type.

fn new_builder(_capacity: usize) -> Self::Builder

Create a new builder with an optional capacity hint.

fn append_value(b: &mut Self::Builder, v: &Self)

Append a non-null value to the builder.

fn append_null(b: &mut Self::Builder)

Append a null to the builder.

fn finish(b: Self::Builder) -> Self::Array

Finish the builder and produce a typed Arrow array.

impl<K> ArrowBinding for Dictionary<K, i64>

where K: DictKey, <K as DictKey>::ArrowKey: ArrowDictionaryKeyType,

type Builder = PrimitiveDictionaryBuilder<<K as DictKey>::ArrowKey, Int64Type>

Concrete Arrow builder type used for this Rust type.

type Array = DictionaryArray<<K as DictKey>::ArrowKey>

Concrete Arrow array type produced by finish.

fn data_type() -> DataType

The Arrow DataType corresponding to this Rust type.

fn new_builder(_capacity: usize) -> Self::Builder

Create a new builder with an optional capacity hint.

fn append_value(b: &mut Self::Builder, v: &Self)

Append a non-null value to the builder.

fn append_null(b: &mut Self::Builder)

Append a null to the builder.

fn finish(b: Self::Builder) -> Self::Array

Finish the builder and produce a typed Arrow array.

impl<K> ArrowBinding for Dictionary<K, i8>

where K: DictKey, <K as DictKey>::ArrowKey: ArrowDictionaryKeyType,

type Builder = PrimitiveDictionaryBuilder<<K as DictKey>::ArrowKey, Int8Type>

Concrete Arrow builder type used for this Rust type.

type Array = DictionaryArray<<K as DictKey>::ArrowKey>

Concrete Arrow array type produced by finish.

fn data_type() -> DataType

The Arrow DataType corresponding to this Rust type.

fn new_builder(_capacity: usize) -> Self::Builder

Create a new builder with an optional capacity hint.

fn append_value(b: &mut Self::Builder, v: &Self)

Append a non-null value to the builder.

fn append_null(b: &mut Self::Builder)

Append a null to the builder.

fn finish(b: Self::Builder) -> Self::Array

Finish the builder and produce a typed Arrow array.

impl<K> ArrowBinding for Dictionary<K, u16>

where K: DictKey, <K as DictKey>::ArrowKey: ArrowDictionaryKeyType,

type Builder = PrimitiveDictionaryBuilder<<K as DictKey>::ArrowKey, UInt16Type>

Concrete Arrow builder type used for this Rust type.

type Array = DictionaryArray<<K as DictKey>::ArrowKey>

Concrete Arrow array type produced by finish.

fn data_type() -> DataType

The Arrow DataType corresponding to this Rust type.

fn new_builder(_capacity: usize) -> Self::Builder

Create a new builder with an optional capacity hint.

fn append_value(b: &mut Self::Builder, v: &Self)

Append a non-null value to the builder.

fn append_null(b: &mut Self::Builder)

Append a null to the builder.

fn finish(b: Self::Builder) -> Self::Array

Finish the builder and produce a typed Arrow array.

impl<K> ArrowBinding for Dictionary<K, u32>

where K: DictKey, <K as DictKey>::ArrowKey: ArrowDictionaryKeyType,

type Builder = PrimitiveDictionaryBuilder<<K as DictKey>::ArrowKey, UInt32Type>

Concrete Arrow builder type used for this Rust type.

type Array = DictionaryArray<<K as DictKey>::ArrowKey>

Concrete Arrow array type produced by finish.

fn data_type() -> DataType

The Arrow DataType corresponding to this Rust type.

fn new_builder(_capacity: usize) -> Self::Builder

Create a new builder with an optional capacity hint.

fn append_value(b: &mut Self::Builder, v: &Self)

Append a non-null value to the builder.

fn append_null(b: &mut Self::Builder)

Append a null to the builder.

fn finish(b: Self::Builder) -> Self::Array

Finish the builder and produce a typed Arrow array.

impl<K> ArrowBinding for Dictionary<K, u64>

where K: DictKey, <K as DictKey>::ArrowKey: ArrowDictionaryKeyType,

type Builder = PrimitiveDictionaryBuilder<<K as DictKey>::ArrowKey, UInt64Type>

Concrete Arrow builder type used for this Rust type.

type Array = DictionaryArray<<K as DictKey>::ArrowKey>

Concrete Arrow array type produced by finish.

fn data_type() -> DataType

The Arrow DataType corresponding to this Rust type.

fn new_builder(_capacity: usize) -> Self::Builder

Create a new builder with an optional capacity hint.

fn append_value(b: &mut Self::Builder, v: &Self)

Append a non-null value to the builder.

fn append_null(b: &mut Self::Builder)

Append a null to the builder.

fn finish(b: Self::Builder) -> Self::Array

Finish the builder and produce a typed Arrow array.

impl<K> ArrowBinding for Dictionary<K, u8>

where K: DictKey, <K as DictKey>::ArrowKey: ArrowDictionaryKeyType,

type Builder = PrimitiveDictionaryBuilder<<K as DictKey>::ArrowKey, UInt8Type>

Concrete Arrow builder type used for this Rust type.

type Array = DictionaryArray<<K as DictKey>::ArrowKey>

Concrete Arrow array type produced by finish.

fn data_type() -> DataType

The Arrow DataType corresponding to this Rust type.

fn new_builder(_capacity: usize) -> Self::Builder

Create a new builder with an optional capacity hint.

fn append_value(b: &mut Self::Builder, v: &Self)

Append a non-null value to the builder.

fn append_null(b: &mut Self::Builder)

Append a null to the builder.

fn finish(b: Self::Builder) -> Self::Array

Finish the builder and produce a typed Arrow array.

impl<K, V> From<V> for Dictionary<K, V>

fn from(value: V) -> Self

Converts to this type from the input type.