sparrow::sparse_union_array Class Reference

Sparse union array implementation without offset buffer. More...

#include <union_array.hpp>

Inheritance diagram for sparrow::sparse_union_array:

Collaboration diagram for sparrow::sparse_union_array:

Public Types
using	base_type = union_array_crtp_base<sparse_union_array>
using	type_id_buffer_type = typename base_type::type_id_buffer_type
Public Types inherited from sparrow::union_array_crtp_base< sparse_union_array >
using	self_type
using	derived_type
using	inner_value_type
using	value_type
using	const_reference
using	functor_type
using	const_functor_type
using	iterator
using	const_iterator
using	const_reverse_iterator
using	size_type
using	type_id_buffer_type

Public Member Functions
template<class... Args> requires (mpl::excludes_copy_and_move_ctor_v<sparse_union_array, Args...>)
	sparse_union_array (Args &&... args)
	Generic constructor for creating sparse union arrays.
SPARROW_API	sparse_union_array (arrow_proxy proxy)
	Constructs sparse union array from Arrow proxy.
Public Member Functions inherited from sparrow::union_array_crtp_base< sparse_union_array >
constexpr std::optional< std::string_view >	name () const
	Gets the optional name of the union array.
SPARROW_CONSTEXPR_CLANG_17 std::optional< key_value_view >	metadata () const
	Gets the metadata associated with the union array.
SPARROW_CONSTEXPR_CLANG_17 value_type	at (size_type i) const
	Gets element at specified position with bounds checking.
SPARROW_CONSTEXPR_CLANG_17 value_type	operator[] (size_type i) const
	Gets element at specified position without bounds checking.
SPARROW_CONSTEXPR_CLANG_17 value_type	operator[] (size_type i)
	Gets mutable element at specified position.
SPARROW_CONSTEXPR_CLANG_17 value_type	front () const
	Gets reference to the first element.
SPARROW_CONSTEXPR_CLANG_17 value_type	back () const
	Gets reference to the last element.
constexpr bool	empty () const
	Checks if the union array is empty.
constexpr size_type	size () const
	Gets the number of elements in the union array.
constexpr iterator	begin ()
	Gets iterator to the beginning of the array.
constexpr iterator	end ()
	Gets iterator to the end of the array.
constexpr const_iterator	begin () const
	Gets const iterator to the beginning of the array.
constexpr const_iterator	end () const
	Gets const iterator to the end of the array.
constexpr const_iterator	cbegin () const
	Gets const iterator to the beginning of the array.
constexpr const_iterator	cend () const
	Gets const iterator to the end of the array.
constexpr const_reverse_iterator	rbegin () const
	Gets reverse iterator to the beginning of reversed array.
constexpr const_reverse_iterator	rend () const
	Gets reverse iterator to the end of reversed array.
constexpr const_reverse_iterator	crbegin () const
	Gets const reverse iterator to the beginning of reversed array.
constexpr const_reverse_iterator	crend () const
	Gets const reverse iterator to the end of reversed array.
constexpr void	zero_null_values (const inner_value_type &value)
	Sets all null values to the specified value.
constexpr auto	type_id_map_from_child_to_type_id (const std::optional< R > &child_index_to_type_id) -> type_id_map
constexpr std::optional< std::string_view >	name () const
	Gets the optional name of the union array.
SPARROW_CONSTEXPR_CLANG_17 std::optional< key_value_view >	metadata () const
	Gets the metadata associated with the union array.
SPARROW_CONSTEXPR_CLANG_17 value_type	at (size_type i) const
	Gets element at specified position with bounds checking.
SPARROW_CONSTEXPR_CLANG_17 value_type	operator[] (size_type i) const
	Gets element at specified position without bounds checking.
SPARROW_CONSTEXPR_CLANG_17 value_type	operator[] (size_type i)
	Gets mutable element at specified position.
SPARROW_CONSTEXPR_CLANG_17 value_type	front () const
	Gets reference to the first element.
SPARROW_CONSTEXPR_CLANG_17 value_type	back () const
	Gets reference to the last element.
constexpr bool	empty () const
	Checks if the union array is empty.
constexpr size_type	size () const
	Gets the number of elements in the union array.
constexpr iterator	begin ()
	Gets iterator to the beginning of the array.
constexpr const_iterator	begin () const
	Gets const iterator to the beginning of the array.
constexpr iterator	end ()
	Gets iterator to the end of the array.
constexpr const_iterator	end () const
	Gets const iterator to the end of the array.
constexpr const_iterator	cbegin () const
	Gets const iterator to the beginning of the array.
constexpr const_iterator	cend () const
	Gets const iterator to the end of the array.
constexpr const_reverse_iterator	rbegin () const
	Gets reverse iterator to the beginning of reversed array.
constexpr const_reverse_iterator	rend () const
	Gets reverse iterator to the end of reversed array.
constexpr const_reverse_iterator	crbegin () const
	Gets const reverse iterator to the beginning of reversed array.
constexpr const_reverse_iterator	crend () const
	Gets const reverse iterator to the end of reversed array.
constexpr void	zero_null_values (const inner_value_type &value)
	Sets all null values to the specified value.
constexpr auto	type_id_map_from_child_to_type_id (const std::optional< R > &child_index_to_type_id) -> type_id_map

Friends
class	union_array_crtp_base< sparse_union_array >

Additional Inherited Members
Protected Types inherited from sparrow::union_array_crtp_base< sparse_union_array >
using	type_id_map
using	children_type
Protected Types inherited from sparrow::crtp_base< D >
using	derived_type = D
Protected Member Functions inherited from sparrow::union_array_crtp_base< sparse_union_array >
constexpr children_type	make_children (arrow_proxy &proxy)
	Creates child array wrappers from Arrow proxy.
	union_array_crtp_base (arrow_proxy proxy)
	Protected constructor from Arrow proxy.
constexpr	union_array_crtp_base (const self_type &rhs)
	Copy constructor.
constexpr self_type &	operator= (const self_type &rhs)
	Copy assignment operator.
constexpr	union_array_crtp_base (self_type &&rhs)=default
constexpr self_type &	operator= (self_type &&rhs)=default
constexpr arrow_proxy &	get_arrow_proxy ()
	Gets mutable reference to the Arrow proxy.
constexpr const arrow_proxy &	get_arrow_proxy () const
	Gets const reference to the Arrow proxy.
constexpr children_type	make_children (arrow_proxy &proxy)
	Creates child array wrappers from Arrow proxy.
	union_array_crtp_base (arrow_proxy proxy)
	Protected constructor from Arrow proxy.
constexpr	union_array_crtp_base (const self_type &rhs)
	Copy constructor.
constexpr	union_array_crtp_base (self_type &&rhs)=default
constexpr self_type &	operator= (const self_type &rhs)
	Copy assignment operator.
constexpr self_type &	operator= (self_type &&rhs)=default
constexpr arrow_proxy &	get_arrow_proxy ()
	Gets mutable reference to the Arrow proxy.
constexpr const arrow_proxy &	get_arrow_proxy () const
	Gets const reference to the Arrow proxy.
Protected Member Functions inherited from sparrow::crtp_base< D >
constexpr derived_type &	derived_cast ()
constexpr const derived_type &	derived_cast () const
Static Protected Member Functions inherited from sparrow::union_array_crtp_base< sparse_union_array >
static constexpr type_id_map	parse_type_id_map (std::string_view format_string)
	Parses type ID mapping from Arrow format string.
static constexpr type_id_map	type_id_map_from_child_to_type_id (const std::optional< R > &child_index_to_type_id)
	Creates type ID mapping from child index to type ID mapping.
static constexpr std::string	make_format_string (bool dense, std::size_t n, const std::optional< R > &child_index_to_type_id)
	Creates Arrow format string for union arrays.
static constexpr type_id_map	parse_type_id_map (std::string_view format_string)
	Parses type ID mapping from Arrow format string.
static constexpr type_id_map	type_id_map_from_child_to_type_id (const std::optional< R > &child_index_to_type_id)
	Creates type ID mapping from child index to type ID mapping.
static constexpr std::string	make_format_string (bool dense, std::size_t n, const std::optional< R > &child_index_to_type_id)
	Creates Arrow format string for union arrays.
Protected Attributes inherited from sparrow::union_array_crtp_base< sparse_union_array >
arrow_proxy	m_proxy
	Internal Arrow proxy.
const std::uint8_t *	p_type_ids
	Pointer to type ID buffer.
children_type	m_children
	Child array wrappers.
std::array< std::uint8_t, TYPE_ID_MAP_SIZE >	m_type_id_map
	Type ID to child index mapping.
arrow_proxy	m_proxy
	Internal Arrow proxy.
const std::uint8_t *	p_type_ids
	Pointer to type ID buffer.
children_type	m_children
	Child array wrappers.
std::array< std::uint8_t, TYPE_ID_MAP_SIZE >	m_type_id_map
	Type ID to child index mapping.
Static Protected Attributes inherited from sparrow::union_array_crtp_base< sparse_union_array >
static constexpr size_t	TYPE_ID_MAP_SIZE
static constexpr size_t	TYPE_ID_MAP_SIZE

Detailed Description

Sparse union array implementation without offset buffer.

Sparse union arrays do not store an offset buffer. Instead, all child arrays have the same length as the union array, and each element directly corresponds to the same position in its child array. This is simpler but less memory efficient when union elements are sparse.

Memory layout:

• Type ID buffer: Maps each element to child array type
• Child arrays: All have the same length as the union array

Related Apache Arrow specification: https://arrow.apache.org/docs/dev/format/Columnar.html#sparse-union

Postcondition

Maintains Arrow sparse union format compatibility ("+us:")

All child arrays have the same length as the union array

Provides simpler access pattern at the cost of memory efficiency

//Create sparse union with int and string children
std::vector<array> children = {int_array, string_array};  // same length as union
type_id_buffer_type type_ids = {0, 1, 0, 1};              // alternating types
 
sparse_union_array union_arr(std::move(children),
                          std::move(type_ids));

Definition at line 803 of file union_array.hpp.

Member Typedef Documentation

base_type

using sparrow::sparse_union_array::base_type = union_array_crtp_base<sparse_union_array>

Definition at line 807 of file union_array.hpp.

type_id_buffer_type

using sparrow::sparse_union_array::type_id_buffer_type = typename base_type::type_id_buffer_type

Definition at line 808 of file union_array.hpp.

Constructor & Destructor Documentation

sparse_union_array() [1/2]

template<class... Args>
requires (mpl::excludes_copy_and_move_ctor_v<sparse_union_array, Args...>)

sparrow::sparse_union_array::sparse_union_array ( Args &&... args )

inlineexplicit

Generic constructor for creating sparse union arrays.

Creates a sparse union array from various input combinations including child arrays, type IDs, and optional type mapping.

Template Parameters

Args	Parameter pack for constructor arguments

Parameters

args	Constructor arguments (children, type_ids, etc.)

Precondition

Args must match one of the create_proxy() overload signatures

Args must exclude copy and move constructor signatures

All child arrays must have the same length

Postcondition

Array is created with the specified children and configuration

Definition at line 826 of file union_array.hpp.

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sparse_union_array() [2/2]

SPARROW_API sparrow::sparse_union_array::sparse_union_array ( arrow_proxy proxy )

explicit

Constructs sparse union array from Arrow proxy.

Parameters

proxy

Arrow proxy containing sparse union array data and schema

Precondition

proxy must contain valid Arrow sparse union array and schema

proxy format must be "+us:..."

proxy must have type ID buffer

All child arrays must have same length as union array

Postcondition

Array is initialized with data from proxy

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Friends And Related Symbol Documentation

union_array_crtp_base< sparse_union_array >

friend class union_array_crtp_base< sparse_union_array >

friend

Definition at line 912 of file union_array.hpp.

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The documentation for this class was generated from the following file:

• /home/runner/work/sparrow/sparrow/include/sparrow/union_array.hpp