trx_undo_t Struct Reference

Transaction undo log memory object; this is protected by the undo_mutex in the corresponding transaction object. More...

#include <trx0undo.h>

Public Types
enum class	Gtid_storage { NONE , COMMIT , PREPARE_AND_COMMIT }
	Undo log may could be allocated to store transaction GTIDs. More...

Public Member Functions
bool	gtid_allocated (bool is_prepare) const
	Check if space for GTID is allocated in undo. More...
std::tuple< int, size_t >	gtid_get_details (bool is_prepare) const
	Get offset and flag for GTID stored in undo. More...
void	set_prepared (const XID *in_xid)
void	set_prepared_in_tc ()
bool	is_prepared () const
	UT_LIST_NODE_T (trx_undo_t) undo_list
	undo log objects in the rollback segment are chained into lists More...

Public Attributes
ulint	id
	undo log slot number within the rollback segment More...
ulint	type
	TRX_UNDO_INSERT or TRX_UNDO_UPDATE. More...
ulint	state
	state of the corresponding undo log segment More...
bool	del_marks
	relevant only in an update undo log: this is true if the transaction may have delete marked records, because of a delete of a row or an update of an indexed field; purge is then necessary; also true if the transaction has updated an externally stored field More...
trx_id_t	trx_id
	id of the trx assigned to the undo log More...
XID	xid
	X/Open XA transaction identification. More...
ulint	flag
	flag for current transaction XID and GTID. More...
Gtid_storage	m_gtid_storage {Gtid_storage::NONE}
	Storage space allocated for GTIDs. More...
bool	dict_operation
	true if a dict operation trx More...
trx_rseg_t *	rseg
	rseg where the undo log belongs More...
space_id_t	space
	space id where the undo log placed More...
page_size_t	page_size
page_no_t	hdr_page_no
	page number of the header page in the undo log More...
ulint	hdr_offset
	header offset of the undo log on the page More...
page_no_t	last_page_no
	page number of the last page in the undo log; this may differ from top_page_no during a rollback More...
ulint	size
	current size in pages More...
ulint	empty
	true if the stack of undo log records is currently empty More...
page_no_t	top_page_no
	page number where the latest undo log record was catenated; during rollback the page from which the latest undo record was chosen More...
ulint	top_offset
	offset of the latest undo record, i.e., the topmost element in the undo log if we think of it as a stack More...
undo_no_t	top_undo_no
	undo number of the latest record More...
buf_block_t *	guess_block
	guess for the buffer block where the top page might reside More...

Detailed Description

Transaction undo log memory object; this is protected by the undo_mutex in the corresponding transaction object.

Member Enumeration Documentation

Gtid_storage

enum class trx_undo_t::Gtid_storage

strong

Undo log may could be allocated to store transaction GTIDs.

Enumerator
NONE
COMMIT
PREPARE_AND_COMMIT

Member Function Documentation

gtid_allocated()

bool trx_undo_t::gtid_allocated

(

bool

is_prepare

)

const

Check if space for GTID is allocated in undo.

Parameters

[in]

is_prepare

if XA prepare GTID

Returns

true iff space for GTID is allocated.

gtid_get_details()

std::tuple< int, size_t > trx_undo_t::gtid_get_details

(

bool

is_prepare

)

const

Get offset and flag for GTID stored in undo.

Parameters

[in]

is_prepare

if XA prepare GTID

Returns

GTID flag and offset in a tuple.

is_prepared()

bool trx_undo_t::is_prepared ( ) const

inline

set_prepared()

void trx_undo_t::set_prepared ( const XID *  in_xid )

inline

set_prepared_in_tc()

void trx_undo_t::set_prepared_in_tc ( )

inline

UT_LIST_NODE_T()

trx_undo_t::UT_LIST_NODE_T

(

trx_undo_t

)

undo log objects in the rollback segment are chained into lists

Member Data Documentation

del_marks

bool trx_undo_t::del_marks

relevant only in an update undo log: this is true if the transaction may have delete marked records, because of a delete of a row or an update of an indexed field; purge is then necessary; also true if the transaction has updated an externally stored field

dict_operation

bool trx_undo_t::dict_operation

true if a dict operation trx

empty

ulint trx_undo_t::empty

true if the stack of undo log records is currently empty

flag

ulint trx_undo_t::flag

flag for current transaction XID and GTID.

Persisted in TRX_UNDO_FLAGS flag of undo header.

guess_block

buf_block_t* trx_undo_t::guess_block

guess for the buffer block where the top page might reside

hdr_offset

ulint trx_undo_t::hdr_offset

header offset of the undo log on the page

hdr_page_no

page_no_t trx_undo_t::hdr_page_no

page number of the header page in the undo log

id

ulint trx_undo_t::id

undo log slot number within the rollback segment

last_page_no

page_no_t trx_undo_t::last_page_no

page number of the last page in the undo log; this may differ from top_page_no during a rollback

m_gtid_storage

Gtid_storage trx_undo_t::m_gtid_storage {Gtid_storage::NONE}

Storage space allocated for GTIDs.

page_size

page_size_t trx_undo_t::page_size

rseg

trx_rseg_t* trx_undo_t::rseg

rseg where the undo log belongs

size

ulint trx_undo_t::size

current size in pages

space

space_id_t trx_undo_t::space

space id where the undo log placed

state

ulint trx_undo_t::state

state of the corresponding undo log segment

top_offset

ulint trx_undo_t::top_offset

offset of the latest undo record, i.e., the topmost element in the undo log if we think of it as a stack

top_page_no

page_no_t trx_undo_t::top_page_no

page number where the latest undo log record was catenated; during rollback the page from which the latest undo record was chosen

top_undo_no

undo_no_t trx_undo_t::top_undo_no

undo number of the latest record

trx_id

trx_id_t trx_undo_t::trx_id

id of the trx assigned to the undo log

type

ulint trx_undo_t::type

TRX_UNDO_INSERT or TRX_UNDO_UPDATE.

xid

XID trx_undo_t::xid

X/Open XA transaction identification.

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

• storage/innobase/include/trx0undo.h
• storage/innobase/include/trx0undo.ic
• storage/innobase/trx/trx0undo.cc