lob::undo_vers_t Struct Reference

The list of modifications to be applied on LOBs to get older versions. More...

#include <lob0undo.h>

Public Member Functions
undo_seq_t *	get_undo_sequence_if_exists (ulint field_no)
	Get the undo log sequence object for the given field number, which represents one blob. More...
undo_seq_t *	get_undo_sequence (ulint field_no)
	Get the undo log sequence object for the given field number, which represents one blob. More...
void	reset ()
	Empty the collected LOB undo information from cache. More...
void	apply (dict_index_t *clust_index, ulint field_no, byte *lob, size_t len, size_t lob_version, page_no_t first_page)
	Apply the undo log record on the given LOB in memory. More...
void	destroy ()
	Destroy the accumulated undo_seq_t objects. More...
bool	is_empty () const
	Check if the undo contained older versions. More...
	~undo_vers_t ()
	Destructor to free the resources. More...

Private Attributes
std::list< undo_seq_t * > *	m_versions = nullptr
	Maintain a list of undo_seq_t objects. More...

Detailed Description

The list of modifications to be applied on LOBs to get older versions.

Given a field number, it should be able to obtain the list of undo information.

Constructor & Destructor Documentation

~undo_vers_t()

lob::undo_vers_t::~undo_vers_t ( )

inline

Destructor to free the resources.

Member Function Documentation

apply()

void lob::undo_vers_t::apply ( dict_index_t *  clust_index, ulint  field_no, byte *  lob, size_t  len, size_t  lob_version, page_no_t  first_page  )

inline

Apply the undo log record on the given LOB in memory.

Parameters

[in]	clust_index	the clust index to which LOB belongs.
[in]	field_no	the field number of the LOB.
[in]	lob	the LOB data.
[in]	len	the length of LOB.
[in]	lob_version	LOB version number.
[in]	first_page	the first page number of LOB.

destroy()

void lob::undo_vers_t::destroy ( )

inline

Destroy the accumulated undo_seq_t objects.

get_undo_sequence()

undo_seq_t * lob::undo_vers_t::get_undo_sequence ( ulint  field_no )

inline

Get the undo log sequence object for the given field number, which represents one blob.

The undo sequence object is allocated if it does not exist.

Parameters

[in]

field_no

the field number of the blob.

Returns

the undo sequence object.

get_undo_sequence_if_exists()

undo_seq_t * lob::undo_vers_t::get_undo_sequence_if_exists ( ulint  field_no )

inline

Get the undo log sequence object for the given field number, which represents one blob.

Parameters

[in]

field_no

the field number of the blob.

Returns

the undo sequence object or nullptr.

is_empty()

bool lob::undo_vers_t::is_empty ( void  ) const

inline

Check if the undo contained older versions.

Returns

true if there are no older versions, false otherwise.

reset()

void lob::undo_vers_t::reset ( void  )

inline

Empty the collected LOB undo information from cache.

Member Data Documentation

m_versions

std::list<undo_seq_t *>* lob::undo_vers_t::m_versions = nullptr

private

Maintain a list of undo_seq_t objects.

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

• storage/innobase/include/lob0undo.h