Struct TypedValueEncoding 

pub struct TypedValueEncoding;

The TypedValueEncoding stores the value of an RDF term as a union of possible types.

Value Spaces

Each RDF literal type has an associated value space (e.g., xsd:int has the value space of 32-bit integers). Transforming the transformation from the lexical space to the value space might be a lossy transformation. For example, the two distinct RDF terms "1"^^xsd::int and "01"^^xsd::int map to the same value. The TypedValueEncoding cannot distinguish between these two terms and therefore should only be used for query parts that do not rely on this distinction.

Future Plans

Currently, the TypedValue encoding has a fixed Arrow DataType. We plan to change that in the future such that users can provide custom encodings for domain-specific literals (e.g., geospatial coordinates).

Implementations

impl TypedValueEncoding

pub fn fields() -> UnionFields

pub fn string_fields() -> Fields

pub fn string_type() -> DataType

pub fn timestamp_fields() -> Fields

pub fn duration_fields() -> Fields

pub fn typed_literal_fields() -> Fields

pub fn encode_term( &self, term: ThinResult<TermRef<'_>>, ) -> DFResult<TypedValueScalar>

Encodes the term as a TypedValueScalar.

Trait Implementations

impl Debug for TypedValueEncoding

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

Formats the value using the given formatter.

impl TermDecoder<TypedValueEncoding> for BooleanTermValueDecoder

type Term<'data> = Boolean

The resulting value type of decoding an RDF term.

fn decode_terms( array: &<TypedValueEncoding as TermEncoding>::Array, ) -> impl Iterator<Item = ThinResult<Self::Term<'_>>>

Allows extracting an iterator over all RDF terms in array that are compatible with this decoder (see TermDecoder for more information).

fn decode_term( scalar: &<TypedValueEncoding as TermEncoding>::Scalar, ) -> ThinResult<Self::Term<'_>>

Allows extracting an iterator over all RDF terms in array that are compatible with this decoder (see TermDecoder for more information).

impl TermDecoder<TypedValueEncoding> for DateTimeTermValueDecoder

type Term<'data> = DateTime

The resulting value type of decoding an RDF term.

fn decode_terms( array: &<TypedValueEncoding as TermEncoding>::Array, ) -> impl Iterator<Item = ThinResult<Self::Term<'_>>>

Allows extracting an iterator over all RDF terms in array that are compatible with this decoder (see TermDecoder for more information).

fn decode_term( scalar: &<TypedValueEncoding as TermEncoding>::Scalar, ) -> ThinResult<Self::Term<'_>>

Allows extracting an iterator over all RDF terms in array that are compatible with this decoder (see TermDecoder for more information).

impl TermDecoder<TypedValueEncoding> for DefaultTypedValueDecoder

type Term<'data> = TypedValueRef<'data>

The resulting value type of decoding an RDF term.

fn decode_terms( array: &<TypedValueEncoding as TermEncoding>::Array, ) -> impl Iterator<Item = ThinResult<Self::Term<'_>>>

Allows extracting an iterator over all RDF terms in array that are compatible with this decoder (see TermDecoder for more information).

fn decode_term( scalar: &<TypedValueEncoding as TermEncoding>::Scalar, ) -> ThinResult<Self::Term<'_>>

Allows extracting an iterator over all RDF terms in array that are compatible with this decoder (see TermDecoder for more information).

impl TermDecoder<TypedValueEncoding> for IntegerTermValueDecoder

type Term<'data> = Integer

The resulting value type of decoding an RDF term.

fn decode_terms( array: &<TypedValueEncoding as TermEncoding>::Array, ) -> impl Iterator<Item = ThinResult<Self::Term<'_>>>

Allows extracting an iterator over all RDF terms in array that are compatible with this decoder (see TermDecoder for more information).

fn decode_term( scalar: &<TypedValueEncoding as TermEncoding>::Scalar, ) -> ThinResult<Self::Term<'_>>

Allows extracting an iterator over all RDF terms in array that are compatible with this decoder (see TermDecoder for more information).

impl TermDecoder<TypedValueEncoding> for NamedNodeRefTermValueDecoder

type Term<'data> = NamedNodeRef<'data>

The resulting value type of decoding an RDF term.

fn decode_terms( array: &<TypedValueEncoding as TermEncoding>::Array, ) -> impl Iterator<Item = ThinResult<Self::Term<'_>>>

Allows extracting an iterator over all RDF terms in array that are compatible with this decoder (see TermDecoder for more information).

fn decode_term( scalar: &<TypedValueEncoding as TermEncoding>::Scalar, ) -> ThinResult<Self::Term<'_>>

Allows extracting an iterator over all RDF terms in array that are compatible with this decoder (see TermDecoder for more information).

impl TermDecoder<TypedValueEncoding> for NumericTermValueDecoder

type Term<'data> = Numeric

The resulting value type of decoding an RDF term.

fn decode_terms( array: &<TypedValueEncoding as TermEncoding>::Array, ) -> impl Iterator<Item = ThinResult<Self::Term<'_>>>

Allows extracting an iterator over all RDF terms in array that are compatible with this decoder (see TermDecoder for more information).

fn decode_term( scalar: &<TypedValueEncoding as TermEncoding>::Scalar, ) -> ThinResult<Self::Term<'_>>

Allows extracting an iterator over all RDF terms in array that are compatible with this decoder (see TermDecoder for more information).

impl TermDecoder<TypedValueEncoding> for SimpleLiteralRefTermValueDecoder

type Term<'data> = SimpleLiteralRef<'data>

The resulting value type of decoding an RDF term.

fn decode_terms( array: &<TypedValueEncoding as TermEncoding>::Array, ) -> impl Iterator<Item = ThinResult<Self::Term<'_>>>

Allows extracting an iterator over all RDF terms in array that are compatible with this decoder (see TermDecoder for more information).

fn decode_term( scalar: &<TypedValueEncoding as TermEncoding>::Scalar, ) -> ThinResult<Self::Term<'_>>

Allows extracting an iterator over all RDF terms in array that are compatible with this decoder (see TermDecoder for more information).

impl TermDecoder<TypedValueEncoding> for StringLiteralRefTermValueDecoder

type Term<'data> = StringLiteralRef<'data>

The resulting value type of decoding an RDF term.

fn decode_terms( array: &<TypedValueEncoding as TermEncoding>::Array, ) -> impl Iterator<Item = ThinResult<Self::Term<'_>>>

Allows extracting an iterator over all RDF terms in array that are compatible with this decoder (see TermDecoder for more information).

fn decode_term( scalar: &<TypedValueEncoding as TermEncoding>::Scalar, ) -> ThinResult<Self::Term<'_>>

Allows extracting an iterator over all RDF terms in array that are compatible with this decoder (see TermDecoder for more information).

impl TermEncoder<TypedValueEncoding> for BlankNodeRefTermValueEncoder

type Term<'data> = BlankNodeRef<'data>

The value type that is being encoded.

fn encode_terms<'data>( terms: impl IntoIterator<Item = ThinResult<Self::Term<'data>>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Array>

Allows encoding an iterator over RDF terms in an Arrow array.

fn encode_term( term: ThinResult<Self::Term<'_>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Scalar>

Allows encoding a scalar RDF term in an Arrow scalar.

impl TermEncoder<TypedValueEncoding> for BlankNodeTermValueEncoder

type Term<'data> = BlankNode

The value type that is being encoded.

fn encode_terms<'data>( terms: impl IntoIterator<Item = ThinResult<Self::Term<'data>>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Array>

Allows encoding an iterator over RDF terms in an Arrow array.

fn encode_term( term: ThinResult<Self::Term<'_>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Scalar>

Allows encoding a scalar RDF term in an Arrow scalar.

impl TermEncoder<TypedValueEncoding> for BooleanTermValueEncoder

type Term<'data> = Boolean

The value type that is being encoded.

fn encode_terms<'data>( terms: impl IntoIterator<Item = ThinResult<Self::Term<'data>>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Array>

Allows encoding an iterator over RDF terms in an Arrow array.

fn encode_term( term: ThinResult<Self::Term<'_>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Scalar>

Allows encoding a scalar RDF term in an Arrow scalar.

impl TermEncoder<TypedValueEncoding> for DateTimeTermValueEncoder

type Term<'data> = DateTime

The value type that is being encoded.

fn encode_terms<'data>( terms: impl IntoIterator<Item = ThinResult<Self::Term<'data>>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Array>

Allows encoding an iterator over RDF terms in an Arrow array.

fn encode_term( term: ThinResult<Self::Term<'_>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Scalar>

Allows encoding a scalar RDF term in an Arrow scalar.

impl TermEncoder<TypedValueEncoding> for DayTimeDurationTermValueEncoder

type Term<'data> = DayTimeDuration

The value type that is being encoded.

fn encode_terms<'data>( terms: impl IntoIterator<Item = ThinResult<Self::Term<'data>>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Array>

Allows encoding an iterator over RDF terms in an Arrow array.

fn encode_term( term: ThinResult<Self::Term<'_>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Scalar>

Allows encoding a scalar RDF term in an Arrow scalar.

impl TermEncoder<TypedValueEncoding> for DecimalTermValueEncoder

type Term<'data> = Decimal

The value type that is being encoded.

fn encode_terms<'data>( terms: impl IntoIterator<Item = ThinResult<Self::Term<'data>>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Array>

Allows encoding an iterator over RDF terms in an Arrow array.

fn encode_term( term: ThinResult<Self::Term<'_>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Scalar>

Allows encoding a scalar RDF term in an Arrow scalar.

impl TermEncoder<TypedValueEncoding> for DefaultTypedValueEncoder

type Term<'data> = TypedValueRef<'data>

The value type that is being encoded.

fn encode_terms<'data>( terms: impl IntoIterator<Item = ThinResult<Self::Term<'data>>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Array>

Allows encoding an iterator over RDF terms in an Arrow array.

fn encode_term( term: ThinResult<Self::Term<'_>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Scalar>

Allows encoding a scalar RDF term in an Arrow scalar.

impl TermEncoder<TypedValueEncoding> for DoubleTermValueEncoder

type Term<'data> = Double

The value type that is being encoded.

fn encode_terms<'data>( terms: impl IntoIterator<Item = ThinResult<Self::Term<'data>>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Array>

Allows encoding an iterator over RDF terms in an Arrow array.

fn encode_term( term: ThinResult<Self::Term<'_>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Scalar>

Allows encoding a scalar RDF term in an Arrow scalar.

impl TermEncoder<TypedValueEncoding> for FloatTermValueEncoder

type Term<'data> = Float

The value type that is being encoded.

fn encode_terms<'data>( terms: impl IntoIterator<Item = ThinResult<Self::Term<'data>>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Array>

Allows encoding an iterator over RDF terms in an Arrow array.

fn encode_term( term: ThinResult<Self::Term<'_>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Scalar>

Allows encoding a scalar RDF term in an Arrow scalar.

impl TermEncoder<TypedValueEncoding> for IntTermValueEncoder

type Term<'data> = Int

The value type that is being encoded.

fn encode_terms<'data>( terms: impl IntoIterator<Item = ThinResult<Self::Term<'data>>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Array>

Allows encoding an iterator over RDF terms in an Arrow array.

fn encode_term( term: ThinResult<Self::Term<'_>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Scalar>

Allows encoding a scalar RDF term in an Arrow scalar.

impl TermEncoder<TypedValueEncoding> for IntegerTermValueEncoder

type Term<'data> = Integer

The value type that is being encoded.

fn encode_terms<'data>( terms: impl IntoIterator<Item = ThinResult<Self::Term<'data>>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Array>

Allows encoding an iterator over RDF terms in an Arrow array.

fn encode_term( term: ThinResult<Self::Term<'_>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Scalar>

Allows encoding a scalar RDF term in an Arrow scalar.

impl TermEncoder<TypedValueEncoding> for LiteralRefTermValueEncoder

type Term<'data> = LiteralRef<'data>

The value type that is being encoded.

fn encode_terms<'data>( terms: impl IntoIterator<Item = ThinResult<Self::Term<'data>>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Array>

Allows encoding an iterator over RDF terms in an Arrow array.

fn encode_term( term: ThinResult<Self::Term<'_>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Scalar>

Allows encoding a scalar RDF term in an Arrow scalar.

impl TermEncoder<TypedValueEncoding> for NamedNodeRefTermValueEncoder

type Term<'data> = NamedNodeRef<'data>

The value type that is being encoded.

fn encode_terms<'data>( terms: impl IntoIterator<Item = ThinResult<Self::Term<'data>>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Array>

Allows encoding an iterator over RDF terms in an Arrow array.

fn encode_term( term: ThinResult<Self::Term<'_>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Scalar>

Allows encoding a scalar RDF term in an Arrow scalar.

impl TermEncoder<TypedValueEncoding> for NamedNodeTermValueEncoder

type Term<'data> = NamedNode

The value type that is being encoded.

fn encode_terms<'data>( terms: impl IntoIterator<Item = ThinResult<Self::Term<'data>>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Array>

Allows encoding an iterator over RDF terms in an Arrow array.

fn encode_term( term: ThinResult<Self::Term<'_>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Scalar>

Allows encoding a scalar RDF term in an Arrow scalar.

impl TermEncoder<TypedValueEncoding> for NumericTypedValueEncoder

type Term<'data> = Numeric

The value type that is being encoded.

fn encode_terms<'data>( terms: impl IntoIterator<Item = ThinResult<Self::Term<'data>>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Array>

Allows encoding an iterator over RDF terms in an Arrow array.

fn encode_term( term: ThinResult<Self::Term<'_>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Scalar>

Allows encoding a scalar RDF term in an Arrow scalar.

impl TermEncoder<TypedValueEncoding> for OwnedStringLiteralTermValueEncoder

type Term<'data> = OwnedStringLiteral

The value type that is being encoded.

fn encode_terms<'data>( terms: impl IntoIterator<Item = ThinResult<Self::Term<'data>>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Array>

Allows encoding an iterator over RDF terms in an Arrow array.

fn encode_term( term: ThinResult<Self::Term<'_>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Scalar>

Allows encoding a scalar RDF term in an Arrow scalar.

impl TermEncoder<TypedValueEncoding> for SimpleLiteralRefTermValueEncoder

type Term<'data> = SimpleLiteralRef<'data>

The value type that is being encoded.

fn encode_terms<'data>( terms: impl IntoIterator<Item = ThinResult<Self::Term<'data>>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Array>

Allows encoding an iterator over RDF terms in an Arrow array.

fn encode_term( term: ThinResult<Self::Term<'_>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Scalar>

Allows encoding a scalar RDF term in an Arrow scalar.

impl TermEncoder<TypedValueEncoding> for StringLiteralRefTermValueEncoder

type Term<'data> = StringLiteralRef<'data>

The value type that is being encoded.

fn encode_terms<'data>( terms: impl IntoIterator<Item = ThinResult<Self::Term<'data>>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Array>

Allows encoding an iterator over RDF terms in an Arrow array.

fn encode_term( term: ThinResult<Self::Term<'_>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Scalar>

Allows encoding a scalar RDF term in an Arrow scalar.

impl TermEncoder<TypedValueEncoding> for TermRefTypedValueEncoder

type Term<'data> = TermRef<'data>

The value type that is being encoded.

fn encode_terms<'data>( terms: impl IntoIterator<Item = ThinResult<Self::Term<'data>>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Array>

Allows encoding an iterator over RDF terms in an Arrow array.

fn encode_term( term: ThinResult<Self::Term<'_>>, ) -> DFResult<<TypedValueEncoding as TermEncoding>::Scalar>

Allows encoding a scalar RDF term in an Arrow scalar.

impl TermEncoding for TypedValueEncoding

type Array = TypedValueArray

Represents a wrapper for Arrow arrays of this encoding. This can be used in conjunction with TermDecoder to obtain the values from an Arrow array.

type Scalar = TypedValueScalar

Represents a wrapper for Arrow scalars of this encoding. This can be used in conjunction with TermDecoder to obtain the values from an Arrow scalar.

fn name(&self) -> EncodingName

Returns the name of the encoding.

fn data_type(&self) -> DataType

Returns the DataType that is used for this encoding.

fn try_new_array(&self, array: ArrayRef) -> DFResult<Self::Array>

Checks whether array contains a value with the correct encoding (i.e., type and possibly metadata checks). If yes, returns an instance of Self::Array. Otherwise, an error is returned.

fn try_new_scalar(&self, scalar: ScalarValue) -> DFResult<Self::Scalar>

Checks whether scalar contains a value with the correct encoding (i.e., type and possibly metadata checks). If yes, returns an instance of Self::Scalar. Otherwise, an error is returned.

fn try_new_datum( &self, value: ColumnarValue, number_rows: usize, ) -> DFResult<EncodingDatum<Self>>

Checks whether value contains a value with the correct encoding (i.e., type and possibly metadata checks). If yes, returns a datum that either wraps an array or a scalar. Otherwise, an error is returned.