trx0trx.h File Reference

The transaction. More...

#include <list>
#include <set>
#include "ha_prototypes.h"
#include "dict0types.h"
#include "sql/handler.h"
#include "trx0types.h"
#include "ut0new.h"
#include "lock0types.h"
#include "log0log.h"
#include "mem0mem.h"
#include "que0types.h"
#include "trx0xa.h"
#include "usr0types.h"
#include "ut0vec.h"
#include "fts0fts.h"
#include "srv0srv.h"
#include "trx0trx.ic"

Go to the source code of this file.

Classes
struct	trx_lock_t
	Latching protocol for trx_lock_t::que_state. More...
struct	trx_undo_ptr_t
	The transaction handle. More...
struct	trx_rsegs_t
	Rollback segments assigned to a transaction for undo logging. More...
struct	TrxVersion
struct	trx_t
struct	commit_node_t
	Commit command node in a query graph. More...
class	TrxInInnoDB
	Track if a transaction is executing inside InnoDB code. More...

Macros
#define	trx_start_if_not_started_xa(t, rw)
#define	trx_start_if_not_started(t, rw)
#define	trx_start_internal(t)
#define	trx_start_internal_read_only(t)
#define	TRX_WEIGHT(t)   ((t)->undo_no + UT_LIST_GET_LEN((t)->lock.trx_locks))
	Calculates the "weight" of a transaction. More...
#define	TRX_QUE_STATE_STR_MAX_LEN   12 /* "ROLLING BACK" */
#define	trx_is_referenced(t)   ((t)->n_ref > 0)
	Check if the transaction is being referenced. More...
#define	trx_lock_wait_timeout_get(t)   ((t)->mysql_thd != NULL ? thd_lock_wait_timeout((t)->mysql_thd) : 0)
	Transactions that aren't started by the MySQL server don't set the trx_t::mysql_thd field. More...
#define	trx_is_autocommit_non_locking(t)   ((t)->auto_commit && (t)->will_lock == 0)
	Determine if the transaction is a non-locking autocommit select (implied read-only). More...
#define	trx_is_ac_nl_ro(t)   ((t)->read_only && trx_is_autocommit_non_locking((t)))
	Determine if the transaction is a non-locking autocommit select with an explicit check for the read-only status. More...
#define	assert_trx_in_rw_list(t)
	Assert that the transaction is in the trx_sys_t::rw_trx_list. More...
#define	check_trx_state(t)
	Check transaction state. More...
#define	assert_trx_is_free(t)
	Check if transaction is free so that it can be re-initialized. More...
#define	assert_trx_is_inactive(t)
	Check if transaction is in-active so that it can be freed and put back to transaction pool. More...
#define	assert_trx_nonlocking_or_in_list(t)
	Assert that an autocommit non-locking select cannot be in the rw_trx_list and that it is a read-only transaction. More...
#define	TRX_ISO_READ_UNCOMMITTED   trx_t::READ_UNCOMMITTED
#define	TRX_ISO_READ_COMMITTED   trx_t::READ_COMMITTED
#define	TRX_ISO_REPEATABLE_READ   trx_t::REPEATABLE_READ
#define	TRX_ISO_SERIALIZABLE   trx_t::SERIALIZABLE
#define	TRX_DUP_IGNORE   1 /* duplicate rows are to be updated */
#define	TRX_DUP_REPLACE   2 /* duplicate rows are to be replaced */
#define	trx_mutex_own(t)   mutex_own(&t->mutex)
	Test if trx->mutex is owned. More...
#define	trx_mutex_enter(t)
	Acquire the trx->mutex. More...
#define	trx_mutex_exit(t)
	Release the trx->mutex. More...

Typedefs
typedef std::vector< ib_lock_t *, ut_allocator< ib_lock_t * > >	lock_pool_t
typedef std::set< dict_table_t *, std::less< dict_table_t * >, ut_allocator< dict_table_t * > >	trx_mod_tables_t
	Type used to store the list of tables that are modified by a given transaction. More...
typedef std::list< TrxVersion, ut_allocator< TrxVersion > >	hit_list_t

Enumerations
enum	trx_rseg_type_t { TRX_RSEG_TYPE_NONE = 0, TRX_RSEG_TYPE_REDO, TRX_RSEG_TYPE_NOREDO }
enum	commit_node_state { COMMIT_NODE_SEND = 1, COMMIT_NODE_WAIT }
	Commit node states. More...

Functions
void	trx_set_flush_observer (trx_t *trx, FlushObserver *observer)
	Set flush observer for the transaction. More...
void	trx_set_detailed_error (trx_t *trx, const char *msg)
	Set detailed error message for the transaction. More...
void	trx_set_detailed_error_from_file (trx_t *trx, FILE *file)
	Set detailed error message for the transaction from a file. More...
UNIV_INLINE const dict_index_t *	trx_get_error_info (const trx_t *trx)
	Retrieves the error_info field from a trx. More...
trx_t *	trx_allocate_for_mysql (void)
	Creates a transaction object for MySQL. More...
trx_t *	trx_allocate_for_background (void)
	Creates a transaction object for background operations by the master thread. More...
void	trx_resurrect_locks ()
	Resurrect table locks for resurrected transactions. More...
void	trx_free_resurrected (trx_t *trx)
	Free and initialize a transaction object instantiated during recovery. More...
void	trx_free_for_background (trx_t *trx)
	Free a transaction that was allocated by background or user threads. More...
void	trx_free_prepared (trx_t *trx)
	At shutdown, frees a transaction object that is in the PREPARED state. More...
void	trx_free_for_mysql (trx_t *trx)
	Free a transaction object for MySQL. More...
void	trx_disconnect_plain (trx_t *trx)
	Disconnect a transaction from MySQL. More...
void	trx_disconnect_prepared (trx_t *trx)
	Disconnect a prepared transaction from MySQL. More...
void	trx_lists_init_at_db_start (void)
	Creates trx objects for transactions and initializes the trx list of trx_sys at database start. More...
void	trx_start_if_not_started_xa_low (trx_t *trx, bool read_write)
	Starts the transaction if it is not yet started. More...
void	trx_start_if_not_started_low (trx_t *trx, bool read_write)
	Starts the transaction if it is not yet started. More...
void	trx_start_internal_low (trx_t *trx)
	Starts a transaction for internal processing. More...
void	trx_start_internal_read_only_low (trx_t *trx)
	Starts a read-only transaction for internal processing. More...
void	trx_commit (trx_t *trx)
	Commits a transaction. More...
void	trx_commit_low (trx_t *trx, mtr_t *mtr)
	Commits a transaction and a mini-transaction. More...
void	trx_cleanup_at_db_startup (trx_t *trx)
	Cleans up a transaction at database startup. More...
dberr_t	trx_commit_for_mysql (trx_t *trx)
	Does the transaction commit for MySQL. More...
dberr_t	trx_prepare_for_mysql (trx_t *trx)
	Does the transaction prepare for MySQL. More...
int	trx_recover_for_mysql (XID *xid_list, ulint len)
	This function is used to find number of prepared transactions and their transaction objects for a recovery. More...
trx_t *	trx_get_trx_by_xid (const XID *xid)
	This function is used to find one X/Open XA distributed transaction which is in the prepared state. More...
void	trx_commit_complete_for_mysql (trx_t *trx)
	If required, flushes the log to disk if we called trx_commit_for_mysql() with trx->flush_log_later == TRUE. More...
void	trx_mark_sql_stat_end (trx_t *trx)
	Marks the latest SQL statement ended. More...
ReadView *	trx_assign_read_view (trx_t *trx)
	Assigns a read view for a consistent read query. More...
UNIV_INLINE ReadView *	trx_get_read_view (trx_t *trx)
UNIV_INLINE const ReadView *	trx_get_read_view (const trx_t *trx)
void	trx_commit_or_rollback_prepare (trx_t *trx)
	Prepares a transaction for commit/rollback. More...
commit_node_t *	trx_commit_node_create (mem_heap_t *heap)
	Creates a commit command node struct. More...
que_thr_t *	trx_commit_step (que_thr_t *thr)
	Performs an execution step for a commit type node in a query graph. More...
void	trx_print_low (FILE *f, const trx_t *trx, ulint max_query_len, ulint n_rec_locks, ulint n_trx_locks, ulint heap_size)
	Prints info about a transaction. More...
void	trx_print_latched (FILE *f, const trx_t *trx, ulint max_query_len)
	Prints info about a transaction. More...
void	trx_print (FILE *f, const trx_t *trx, ulint max_query_len)
	Prints info about a transaction. More...
UNIV_INLINE enum trx_dict_op_t	trx_get_dict_operation (const trx_t *trx)
	Determine if a transaction is a dictionary operation. More...
UNIV_INLINE void	trx_set_dict_operation (trx_t *trx, enum trx_dict_op_t op)
	Flag a transaction a dictionary operation. More...
UNIV_INLINE bool	trx_state_eq (const trx_t *trx, trx_state_t state)
	Determines if a transaction is in the given state. More...
ibool	trx_assert_started (const trx_t *trx)
	Asserts that a transaction has been started. More...
ibool	trx_is_interrupted (const trx_t *trx)
	Determines if the currently running transaction has been interrupted. More...
ibool	trx_is_strict (trx_t *trx)
	Determines if the currently running transaction is in strict mode. More...
bool	trx_weight_ge (const trx_t *a, const trx_t *b)
	Compares the "weight" (or size) of two transactions. More...
UNIV_INLINE const char *	trx_get_que_state_str (const trx_t *trx)
	Retrieves transaction's que state in a human readable string. More...
UNIV_INLINE trx_id_t	trx_get_id_for_print (const trx_t *trx)
	Retreieves the transaction ID. More...
void	trx_assign_rseg_temp (trx_t *trx)
	Assign a temp-tablespace bound rollback-segment to a transaction. More...
void	trx_pool_init ()
	Create the trx_t pool. More...
void	trx_pool_close ()
	Destroy the trx_t pool. More...
void	trx_set_rw_mode (trx_t *trx)
	Set the transaction as a read-write transaction if it is not already tagged as such. More...
UNIV_INLINE trx_t *	trx_reference (trx_t *trx, bool do_ref_count)
	Increase the reference count. More...
UNIV_INLINE void	trx_release_reference (trx_t *trx)
	Release the transaction. More...
UNIV_INLINE const trx_t *	trx_arbitrate (const trx_t *requestor, const trx_t *holder)
UNIV_INLINE bool	trx_is_high_priority (const trx_t *trx)
void	trx_kill_blocking (trx_t *trx)
	Kill all transactions that are blocking this transaction from acquiring locks. More...
UNIV_INLINE bool	trx_is_rseg_updated (const trx_t *trx)
	Check if redo/noredo rseg is modified for insert/update. More...
bool	trx_is_started (const trx_t *trx)
	Check if transaction is started. More...

Variables
sess_t *	trx_dummy_sess
	Dummy session used currently in MySQL interface. More...

Detailed Description

The transaction.

Created 3/26/1996 Heikki Tuuri

Macro Definition Documentation

assert_trx_in_rw_list

#define assert_trx_in_rw_list

(

t

)

Value:

do {                                                   \
    ut_ad(!(t)->read_only);                              \
    ut_ad((t)->in_rw_trx_list ==                         \
          !((t)->read_only || !(t)->rsegs.m_redo.rseg)); \
    check_trx_state(t);                                  \
  } while (0)

Assert that the transaction is in the trx_sys_t::rw_trx_list.

assert_trx_is_free

#define assert_trx_is_free

(

t

)

Value:

do {                                                   \
    ut_ad(trx_state_eq((t), TRX_STATE_NOT_STARTED) ||    \
          trx_state_eq((t), TRX_STATE_FORCED_ROLLBACK)); \
    ut_ad(!trx_is_rseg_updated(trx));                    \
    ut_ad(!MVCC::is_view_active((t)->read_view));        \
    ut_ad((t)->lock.wait_thr == NULL);                   \
    ut_ad(UT_LIST_GET_LEN((t)->lock.trx_locks) == 0);    \
    ut_ad((t)->dict_operation == TRX_DICT_OP_NONE);      \
  } while (0)

Check if transaction is free so that it can be re-initialized.

Parameters

t	transaction handle

assert_trx_is_inactive

#define assert_trx_is_inactive

(

t

)

Value:

do {                                         \
    assert_trx_is_free((t));                   \
    ut_ad((t)->dict_operation_lock_mode == 0); \
  } while (0)

Check if transaction is in-active so that it can be freed and put back to transaction pool.

Parameters

t	transaction handle

assert_trx_nonlocking_or_in_list

#define assert_trx_nonlocking_or_in_list

(

t

)

Value:

do {                                              \
    if (trx_is_autocommit_non_locking(t)) {         \
      trx_state_t t_state = (t)->state;             \
      ut_ad((t)->read_only);                        \
      ut_ad(!(t)->is_recovered);                    \
      ut_ad(!(t)->in_rw_trx_list);                  \
      ut_ad((t)->in_mysql_trx_list);                \
      ut_ad(t_state == TRX_STATE_NOT_STARTED ||     \
            t_state == TRX_STATE_FORCED_ROLLBACK || \
            t_state == TRX_STATE_ACTIVE);           \
    } else {                                        \
      check_trx_state(t);                           \
    }                                               \
  } while (0)

Assert that an autocommit non-locking select cannot be in the rw_trx_list and that it is a read-only transaction.

The tranasction must be in the mysql_trx_list.

check_trx_state

#define check_trx_state

(

t

)

Value:

do {                                          \
    ut_ad(!trx_is_autocommit_non_locking((t))); \
    switch ((t)->state) {                       \
      case TRX_STATE_PREPARED:                  \
        /* fall through */                      \
      case TRX_STATE_ACTIVE:                    \
      case TRX_STATE_COMMITTED_IN_MEMORY:       \
        continue;                               \
      case TRX_STATE_NOT_STARTED:               \
      case TRX_STATE_FORCED_ROLLBACK:           \
        break;                                  \
    }                                           \
    ut_error;                                   \
  } while (0)

Check transaction state.

TRX_DUP_IGNORE

#define TRX_DUP_IGNORE   1 /* duplicate rows are to be updated */

TRX_DUP_REPLACE

#define TRX_DUP_REPLACE   2 /* duplicate rows are to be replaced */

trx_is_ac_nl_ro

#define trx_is_ac_nl_ro

(

t

)

((t)->read_only && trx_is_autocommit_non_locking((t)))

Determine if the transaction is a non-locking autocommit select with an explicit check for the read-only status.

Parameters

t	transaction

Returns

true if non-locking autocommit read-only transaction.

trx_is_autocommit_non_locking

#define trx_is_autocommit_non_locking

(

t

)

((t)->auto_commit && (t)->will_lock == 0)

Determine if the transaction is a non-locking autocommit select (implied read-only).

Parameters

t	transaction

Returns

true if non-locking autocommit select transaction.

trx_is_referenced

#define trx_is_referenced

(

t

)

((t)->n_ref > 0)

Check if the transaction is being referenced.

TRX_ISO_READ_COMMITTED

#define TRX_ISO_READ_COMMITTED   trx_t::READ_COMMITTED

TRX_ISO_READ_UNCOMMITTED

#define TRX_ISO_READ_UNCOMMITTED   trx_t::READ_UNCOMMITTED

TRX_ISO_REPEATABLE_READ

#define TRX_ISO_REPEATABLE_READ   trx_t::REPEATABLE_READ

TRX_ISO_SERIALIZABLE

#define TRX_ISO_SERIALIZABLE   trx_t::SERIALIZABLE

trx_lock_wait_timeout_get

#define trx_lock_wait_timeout_get

(

t

)

((t)->mysql_thd != NULL ? thd_lock_wait_timeout((t)->mysql_thd) : 0)

Transactions that aren't started by the MySQL server don't set the trx_t::mysql_thd field.

For such transactions we set the lock wait timeout to 0 instead of the user configured value that comes from innodb_lock_wait_timeout via trx_t::mysql_thd.

Parameters

t	transaction

Returns

lock wait timeout in seconds

trx_mutex_enter

#define trx_mutex_enter

(

t

)

Value:

do {                      \
    mutex_enter(&t->mutex); \
  } while (0)

Acquire the trx->mutex.

trx_mutex_exit

#define trx_mutex_exit

(

t

)

Value:

do {                     \
    mutex_exit(&t->mutex); \
  } while (0)

Release the trx->mutex.

trx_mutex_own

#define trx_mutex_own

(

t

)

mutex_own(&t->mutex)

Test if trx->mutex is owned.

TRX_QUE_STATE_STR_MAX_LEN

#define TRX_QUE_STATE_STR_MAX_LEN   12 /* "ROLLING BACK" */

trx_start_if_not_started

#define trx_start_if_not_started	(		t,
			rw
	)

Value:

do {                                     \
    (t)->start_line = __LINE__;            \
    (t)->start_file = __FILE__;            \
    trx_start_if_not_started_low((t), rw); \
  } while (false)

trx_start_if_not_started_xa

#define trx_start_if_not_started_xa	(		t,
			rw
	)

Value:

do {                                        \
    (t)->start_line = __LINE__;               \
    (t)->start_file = __FILE__;               \
    trx_start_if_not_started_xa_low((t), rw); \
  } while (false)

trx_start_internal

#define trx_start_internal

(

t

)

Value:

do {                           \
    (t)->start_line = __LINE__;  \
    (t)->start_file = __FILE__;  \
    trx_start_internal_low((t)); \
  } while (false)

trx_start_internal_read_only

#define trx_start_internal_read_only

(

t

)

Value:

do {                                   \
    (t)->start_line = __LINE__;          \
    (t)->start_file = __FILE__;          \
    trx_start_internal_read_only_low(t); \
  } while (false)

TRX_WEIGHT

#define TRX_WEIGHT

(

t

)

((t)->undo_no + UT_LIST_GET_LEN((t)->lock.trx_locks))

Calculates the "weight" of a transaction.

The weight of one transaction is estimated as the number of altered rows + the number of locked rows.

Parameters

t	transaction

Returns

transaction weight

Typedef Documentation

hit_list_t

typedef std::list<TrxVersion, ut_allocator<TrxVersion> > hit_list_t

lock_pool_t

typedef std::vector<ib_lock_t *, ut_allocator<ib_lock_t *> > lock_pool_t

trx_mod_tables_t

typedef std::set<dict_table_t *, std::less<dict_table_t *>, ut_allocator<dict_table_t *> > trx_mod_tables_t

Type used to store the list of tables that are modified by a given transaction.

We store pointers to the table objects in memory because we know that a table object will not be destroyed while a transaction that modified it is running.

Enumeration Type Documentation

commit_node_state

enum commit_node_state

Commit node states.

Enumerator
COMMIT_NODE_SEND	about to send a commit signal to the transaction
COMMIT_NODE_WAIT	commit signal sent to the transaction, waiting for completion

trx_rseg_type_t

enum trx_rseg_type_t

Enumerator
TRX_RSEG_TYPE_NONE	void rollback segment type.
TRX_RSEG_TYPE_REDO	redo rollback segment.
TRX_RSEG_TYPE_NOREDO	non-redo rollback segment.

Function Documentation

trx_allocate_for_background()

trx_t* trx_allocate_for_background

(

void

)

Creates a transaction object for background operations by the master thread.

Returns

own: transaction object

trx_allocate_for_mysql()

trx_t* trx_allocate_for_mysql

(

void

)

Creates a transaction object for MySQL.

Returns

own: transaction object

trx_arbitrate()

UNIV_INLINE const trx_t* trx_arbitrate	(	const trx_t *	requestor,
		const trx_t *	holder
	)

Parameters

[in]	requestor	Transaction requesting the lock
[in]	holder	Transaction holding the lock

Returns

the transaction that will be rolled back, null don't care

trx_assert_started()

ibool trx_assert_started

(

const trx_t *

trx

)

Asserts that a transaction has been started.

The caller must hold trx_sys->mutex.

Returns

true if started

Parameters

trx	in: transaction

trx_assign_read_view()

ReadView* trx_assign_read_view

(

trx_t *

trx

)

Assigns a read view for a consistent read query.

All the consistent reads within the same transaction will get the same read view, which is created when this function is first called for a new started transaction. in: active transaction

All the consistent reads within the same transaction will get the same read view, which is created when this function is first called for a new started transaction.

Returns

consistent read view

Parameters

trx	in/out: active transaction

trx_assign_rseg_temp()

void trx_assign_rseg_temp

(

trx_t *

trx

)

Assign a temp-tablespace bound rollback-segment to a transaction.

Parameters

[in,out]

trx

transaction that involves write to temp-table.

trx_cleanup_at_db_startup()

void trx_cleanup_at_db_startup

(

trx_t *

trx

)

Cleans up a transaction at database startup.

The cleanup is needed if the transaction already got to the middle of a commit when the database crashed, and we cannot roll it back. in: transaction

The cleanup is needed if the transaction already got to the middle of a commit when the database crashed, and we cannot roll it back.

Parameters

trx	in: transaction

trx_commit()

void trx_commit

(

trx_t *

trx

)

Commits a transaction.

in/out: transaction

Parameters

trx	in/out: transaction

trx_commit_complete_for_mysql()

void trx_commit_complete_for_mysql

(

trx_t *

trx

)

If required, flushes the log to disk if we called trx_commit_for_mysql() with trx->flush_log_later == TRUE.

in/out: transaction

Parameters

trx	in/out: transaction

trx_commit_for_mysql()

dberr_t trx_commit_for_mysql

(

trx_t *

trx

)

Does the transaction commit for MySQL.

Returns

DB_SUCCESS or error number in/out: transaction

DB_SUCCESS or error number

Parameters

trx	in/out: transaction

trx_commit_low()

void trx_commit_low	(	trx_t *	trx,
		mtr_t *	mtr
	)

Commits a transaction and a mini-transaction.

in/out: mini-transaction (will be committed), or NULL if trx made no modifications

Parameters

trx	in/out: transaction
mtr	in/out: mini-transaction (will be committed), or NULL if trx made no modifications

trx_commit_node_create()

commit_node_t* trx_commit_node_create

(

mem_heap_t *

heap

)

Creates a commit command node struct.

Returns

own: commit node struct in: mem heap where created

own: commit node struct

Parameters

heap	in: mem heap where created

trx_commit_or_rollback_prepare()

void trx_commit_or_rollback_prepare

(

trx_t *

trx

)

Prepares a transaction for commit/rollback.

in/out: transaction

Parameters

trx	in/out: transaction

trx_commit_step()

que_thr_t* trx_commit_step

(

que_thr_t *

thr

)

Performs an execution step for a commit type node in a query graph.

Returns

query thread to run next, or NULL in: query thread

query thread to run next, or NULL

Parameters

thr	in: query thread

trx_disconnect_plain()

void trx_disconnect_plain ( trx_t *  trx )

inline

Disconnect a transaction from MySQL.

Parameters

[in,out]

trx

transaction

trx_disconnect_prepared()

void trx_disconnect_prepared

(

trx_t *

trx

)

Disconnect a prepared transaction from MySQL.

Parameters

[in,out]

trx

transaction

trx_free_for_background()

void trx_free_for_background

(

trx_t *

trx

)

Free a transaction that was allocated by background or user threads.

Parameters

[in,out]

trx

transaction object to free

trx_free_for_mysql()

void trx_free_for_mysql

(

trx_t *

trx

)

Free a transaction object for MySQL.

Parameters

[in,out]

trx

transaction

trx_free_prepared()

void trx_free_prepared

(

trx_t *

trx

)

At shutdown, frees a transaction object that is in the PREPARED state.

in, own: trx object

Parameters

trx	in, own: trx object

trx_free_resurrected()

void trx_free_resurrected

(

trx_t *

trx

)

Free and initialize a transaction object instantiated during recovery.

Parameters

[in,out]

trx

transaction object to free and initialize

trx_get_dict_operation()

UNIV_INLINE enum trx_dict_op_t trx_get_dict_operation

(

const trx_t *

trx

)

Determine if a transaction is a dictionary operation.

Returns

dictionary operation mode

Parameters

trx	in: transaction

trx_get_error_info()

UNIV_INLINE const dict_index_t* trx_get_error_info

(

const trx_t *

trx

)

Retrieves the error_info field from a trx.

Returns

the error info in: trx object

trx_get_id_for_print()

UNIV_INLINE trx_id_t trx_get_id_for_print

(

const trx_t *

trx

)

Retreieves the transaction ID.

In a given point in time it is guaranteed that IDs of the running transactions are unique. The values returned by this function for readonly transactions may be reused, so a subsequent RO transaction may get the same ID as a RO transaction that existed in the past. The values returned by this function should be used for printing purposes only.

Parameters

[in]

trx

transaction whose id to retrieve

Returns

transaction id

trx_get_que_state_str()

UNIV_INLINE const char* trx_get_que_state_str

(

const trx_t *

trx

)

Retrieves transaction's que state in a human readable string.

The string should not be free()'d or modified.

Returns

string in the data segment in: transaction

trx_get_read_view() [1/2]

UNIV_INLINE ReadView* trx_get_read_view

(

trx_t *

trx

)

Returns

the transaction's read view or NULL if one not assigned.

trx_get_read_view() [2/2]

UNIV_INLINE const ReadView* trx_get_read_view

(

const trx_t *

trx

)

Returns

the transaction's read view or NULL if one not assigned.

trx_get_trx_by_xid()

trx_t* trx_get_trx_by_xid

(

const XID *

xid

)

This function is used to find one X/Open XA distributed transaction which is in the prepared state.

Returns

trx or NULL; on match, the trx->xid will be invalidated; note that the trx may have been committed, unless the caller is holding lock_sys->mutex in: X/Open XA transaction identifier

trx or NULL; on match, the trx->xid will be invalidated; note that the trx may have been committed, unless the caller is holding lock_sys->mutex

Parameters

xid	in: X/Open XA transaction identifier

trx_is_high_priority()

UNIV_INLINE bool trx_is_high_priority

(

const trx_t *

trx

)

Parameters

[in]

trx

Transaction to check

Returns

true if the transaction is a high priority transaction.

trx_is_interrupted()

ibool trx_is_interrupted

(

const trx_t *

trx

)

Determines if the currently running transaction has been interrupted.

Returns

true if interrupted in: transaction

true if interrupted

Parameters

trx	in: transaction

trx_is_rseg_updated()

UNIV_INLINE bool trx_is_rseg_updated

(

const trx_t *

trx

)

Check if redo/noredo rseg is modified for insert/update.

Parameters

[in]

trx

Transaction to check

trx_is_started()

bool trx_is_started ( const trx_t *  trx )

inline

Check if transaction is started.

Parameters

[in]

trx

Transaction whose state we need to check

Returns

true if transaction is in state started

trx_is_strict()

ibool trx_is_strict

(

trx_t *

trx

)

Determines if the currently running transaction is in strict mode.

Returns

true if strict in: transaction

true if strict

Parameters

trx	in: transaction

trx_kill_blocking()

void trx_kill_blocking

(

trx_t *

trx

)

Kill all transactions that are blocking this transaction from acquiring locks.

Parameters

[in,out]

trx

High priority transaction

Kill the transactions in the lock acquisition order old -> new.

trx_lists_init_at_db_start()

void trx_lists_init_at_db_start

(

void

)

Creates trx objects for transactions and initializes the trx list of trx_sys at database start.

Rollback segment and undo log lists must already exist when this function is called, because the lists of transactions to be rolled back or cleaned up are built based on the undo log lists.

Rollback segments and undo log lists must already exist when this function is called, because the lists of transactions to be rolled back or cleaned up are built based on the undo log lists.

trx_mark_sql_stat_end()

void trx_mark_sql_stat_end

(

trx_t *

trx

)

Marks the latest SQL statement ended.

in: trx handle

Parameters

trx	in: trx handle

trx_pool_close()

void trx_pool_close

(

)

Destroy the trx_t pool.

trx_pool_init()

void trx_pool_init

(

)

Create the trx_t pool.

trx_prepare_for_mysql()

dberr_t trx_prepare_for_mysql

(

trx_t *

trx

)

Does the transaction prepare for MySQL.

Parameters

[in,out]

trx

Transaction instance to prepare

trx_print()

void trx_print	(	FILE *	f,
		const trx_t *	trx,
		ulint	max_query_len
	)

Prints info about a transaction.

Acquires and releases lock_sys->mutex and trx_sys->mutex. in: max query length to print, or 0 to use the default max length

Acquires and releases lock_sys->mutex and trx_sys->mutex.

Parameters

f	in: output stream
trx	in: transaction
max_query_len	in: max query length to print, or 0 to use the default max length

trx_print_latched()

void trx_print_latched	(	FILE *	f,
		const trx_t *	trx,
		ulint	max_query_len
	)

Prints info about a transaction.

The caller must hold lock_sys->mutex and trx_sys->mutex. When possible, use trx_print() instead. in: max query length to print, or 0 to use the default max length

The caller must hold lock_sys->mutex and trx_sys->mutex. When possible, use trx_print() instead.

Parameters

f	in: output stream
trx	in: transaction
max_query_len	in: max query length to print, or 0 to use the default max length

trx_print_low()

void trx_print_low	(	FILE *	f,
		const trx_t *	trx,
		ulint	max_query_len,
		ulint	n_rec_locks,
		ulint	n_trx_locks,
		ulint	heap_size
	)

Prints info about a transaction.

Caller must hold trx_sys->mutex. in: mem_heap_get_size(trx->lock.lock_heap)

Caller must hold trx_sys->mutex.

Parameters

f	in: output stream
trx	in: transaction
max_query_len	in: max query length to print, or 0 to use the default max length
n_rec_locks	in: lock_number_of_rows_locked(&trx->lock)
n_trx_locks	in: length of trx->lock.trx_locks
heap_size	in: mem_heap_get_size(trx->lock.lock_heap)

trx_recover_for_mysql()

int trx_recover_for_mysql	(	XID *	xid_list,
		ulint	len
	)

This function is used to find number of prepared transactions and their transaction objects for a recovery.

Returns

number of prepared transactions in: number of slots in xid_list

number of prepared transactions stored in xid_list

Parameters

xid_list	in/out: prepared transactions
len	in: number of slots in xid_list

trx_reference()

UNIV_INLINE trx_t* trx_reference	(	trx_t *	trx,
		bool	do_ref_count
	)

Increase the reference count.

If the transaction is in state TRX_STATE_COMMITTED_IN_MEMORY then the transaction is considered committed and the reference count is not incremented.

Parameters

trx	Transaction that is being referenced
do_ref_count	Increment the reference iff this is true

Returns

transaction instance if it is not committed

trx_release_reference()

UNIV_INLINE void trx_release_reference

(

trx_t *

trx

)

Release the transaction.

Decrease the reference count.

Parameters

trx	Transaction that is being released

trx_resurrect_locks()

void trx_resurrect_locks

(

)

Resurrect table locks for resurrected transactions.

trx_set_detailed_error()

void trx_set_detailed_error	(	trx_t *	trx,
		const char *	msg
	)

Set detailed error message for the transaction.

in: detailed error message

Parameters

trx	in: transaction struct
msg	in: detailed error message

trx_set_detailed_error_from_file()

void trx_set_detailed_error_from_file	(	trx_t *	trx,
		FILE *	file
	)

Set detailed error message for the transaction from a file.

Note that the file is rewinded before reading from it. in: file to read message from

Note that the file is rewinded before reading from it.

Parameters

trx	in: transaction struct
file	in: file to read message from

trx_set_dict_operation()

UNIV_INLINE void trx_set_dict_operation	(	trx_t *	trx,
		enum trx_dict_op_t	op
	)

Flag a transaction a dictionary operation.

Parameters

[in,out]	trx	transaction
[in]	op	operation, not TRX_DICT_OP_NONE

trx_set_flush_observer()

void trx_set_flush_observer	(	trx_t *	trx,
		FlushObserver *	observer
	)

Set flush observer for the transaction.

Parameters

[in,out]	trx	transaction struct
[in]	observer	flush observer

trx_set_rw_mode()

void trx_set_rw_mode

(

trx_t *

trx

)

Set the transaction as a read-write transaction if it is not already tagged as such.

Parameters

[in,out]

trx

Transaction that needs to be "upgraded" to RW from RO

Read-only transactions that are writing to temporary tables are assigned an ID and a rollback segment but are not added to the trx read-write list because their updates should not be visible to other transactions and therefore their changes can be ignored by by MVCC.

Parameters

trx	in/out: transaction that is RW

trx_start_if_not_started_low()

void trx_start_if_not_started_low	(	trx_t *	trx,
		bool	read_write
	)

Starts the transaction if it is not yet started.

in: true if read write transaction

Parameters

trx	in: transaction
read_write	in: true if read write transaction

trx_start_if_not_started_xa_low()

void trx_start_if_not_started_xa_low	(	trx_t *	trx,
		bool	read_write
	)

Starts the transaction if it is not yet started.

in: true if read write transaction

Parameters

trx	in/out: transaction
read_write	in: true if read write transaction

trx_start_internal_low()

void trx_start_internal_low

(

trx_t *

trx

)

Starts a transaction for internal processing.

in/out: transaction

Parameters

trx	in/out: transaction

trx_start_internal_read_only_low()

void trx_start_internal_read_only_low

(

trx_t *

trx

)

Starts a read-only transaction for internal processing.

Parameters

[in,out]

trx

transaction to be started

trx_state_eq()

UNIV_INLINE bool trx_state_eq	(	const trx_t *	trx,
		trx_state_t	state
	)

Determines if a transaction is in the given state.

The caller must hold trx_sys->mutex, or it must be the thread that is serving a running transaction. A running RW transaction must be in trx_sys->rw_trx_list.

Returns

true if trx->state == state

Parameters

trx	in: transaction
state	in: state

trx_weight_ge()

bool trx_weight_ge	(	const trx_t *	a,
		const trx_t *	b
	)

Compares the "weight" (or size) of two transactions.

Transactions that have edited non-transactional tables are considered heavier than ones that have not.

Returns

true if weight(a) >= weight(b) in: the transaction to be compared

Transactions that have edited non-transactional tables are considered heavier than ones that have not.

Returns

true if weight(a) >= weight(b)

Parameters

a	in: transaction to be compared
b	in: transaction to be compared

Variable Documentation

trx_dummy_sess

sess_t* trx_dummy_sess

Dummy session used currently in MySQL interface.