cppgres::tuple_descriptor Struct Reference

Tuple descriptor operator. More...

#include <record.hpp>

Public Member Functions
	tuple_descriptor (int nattrs, memory_context ctx=memory_context())
	Create a tuple descriptor for a given number of attributes.
	tuple_descriptor (TupleDesc tupdesc, bool blessed=true)
	Create a tuple descriptor for a given TupleDesc
	tuple_descriptor (tuple_descriptor &other)
	Copy constructor.
	tuple_descriptor (tuple_descriptor &&other)
	Move constructor.
tuple_descriptor &	operator= (const tuple_descriptor &other)
	Copy assignment.
int	attributes () const
	Number of attributes.
::FormData_pg_attribute &	operator[] (int n) const
	Get a reference to Form_pg_attribute
type	get_type (int n) const
void	set_type (int n, const type &type)
	Set attribute type.
std::string_view	get_name (int n)
void	set_name (int n, const name &name)
	Set attribute name.
	operator TupleDesc ()
	returns a pointer to TupleDesc
bool	equal_types (const tuple_descriptor &other)
	Determines whether two tuple descriptors have equal row types.
bool	operator== (const tuple_descriptor &other)
	Compare two TupleDesc structures for logical equality.
bool	is_blessed () const
	Returns true if the tuple descriptor is blessed.
	operator TupleDesc () const

Detailed Description

Tuple descriptor operator.

Allows to create new or manipulate existing tuple descriptors

Constructor & Destructor Documentation

tuple_descriptor() [1/3]

cppgres::tuple_descriptor::tuple_descriptor ( int  nattrs, memory_context  ctx = memory_context()  )

inline

Create a tuple descriptor for a given number of attributes.

Parameters

nattrs	number of attributes
ctx	memory context, current transaction context by default

tuple_descriptor() [2/3]

cppgres::tuple_descriptor::tuple_descriptor ( TupleDesc  tupdesc, bool  blessed = true  )

inline

Create a tuple descriptor for a given TupleDesc

Parameters

tupdesc	existing attribute
blessed	true if already blessed (default)

tuple_descriptor() [3/3]

cppgres::tuple_descriptor::tuple_descriptor ( tuple_descriptor &  other )

inline

Copy constructor.

Creates a copy instance of the tuple descriptor in the current memory contet

Member Function Documentation

equal_types()

bool cppgres::tuple_descriptor::equal_types ( const tuple_descriptor &  other )

inline

Determines whether two tuple descriptors have equal row types.

This is used to check whether two record types are compatible, whether function return row types are the same, and other similar situations.

operator TupleDesc()

cppgres::tuple_descriptor::operator TupleDesc ( )

inline

returns a pointer to TupleDesc

At this point, it'll be prepared and blessed.

operator=()

tuple_descriptor & cppgres::tuple_descriptor::operator= ( const tuple_descriptor &  other )

inline

Copy assignment.

Creates a copy instance of the tuple descriptor in the current memory contet

operator==()

bool cppgres::tuple_descriptor::operator== ( const tuple_descriptor &  other )

inline

Compare two TupleDesc structures for logical equality.

Note

This includes checking attribute names.

operator[]()

::FormData_pg_attribute & cppgres::tuple_descriptor::operator[] ( int  n ) const

inline

Get a reference to Form_pg_attribute

Exceptions

std::out_of_range

when attribute index is out of range

set_name()

void cppgres::tuple_descriptor::set_name ( int  n, const name &  name  )

inline

Set attribute name.

Parameters

n	Zero-based attribute index
name	new attribute name

Exceptions

std::out_of_range

when attribute index is out of range

set_type()

void cppgres::tuple_descriptor::set_type ( int  n, const type &  type  )

inline

Set attribute type.

Parameters

n	Zero-based attribute index
type	new attribute type

Exceptions

std::out_of_range

when attribute index is out of range

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

• src/cppgres/record.hpp