row0undo.h File Reference

#include "univ.i"
#include "mtr0mtr.h"
#include "trx0sys.h"
#include "btr0types.h"
#include "btr0pcur.h"
#include "dict0types.h"
#include "trx0types.h"
#include "que0types.h"
#include "row0types.h"
#include "row0undo.ic"

Include dependency graph for row0undo.h:

Go to the source code of this file.

Data Structures
struct	undo_node_t

Enumerations
enum	undo_exec { UNDO_NODE_FETCH_NEXT = 1, UNDO_NODE_INSERT, UNDO_NODE_MODIFY }

Functions
UNIV_INTERN undo_node_t *	row_undo_node_create (trx_t *trx, que_thr_t *parent, mem_heap_t *heap)
UNIV_INTERN ibool	row_undo_search_clust_to_pcur (undo_node_t *node)
UNIV_INTERN que_thr_t *	row_undo_step (que_thr_t *thr)

Detailed Description

Row undo

Created 1/8/1997 Heikki Tuuri

Enumeration Type Documentation

enum undo_exec

Execution state of an undo node

Enumerator:

UNDO_NODE_FETCH_NEXT	we should fetch the next undo log record
UNDO_NODE_INSERT	undo a fresh insert of a row to a table
UNDO_NODE_MODIFY	undo a modify operation (DELETE or UPDATE) on a row of a table

Function Documentation

UNIV_INTERN undo_node_t* row_undo_node_create	(	trx_t *	trx,
		que_thr_t *	parent,
		mem_heap_t *	heap
	)

Creates a row undo node to a query graph.

Returns

own: undo node in: memory heap where created

Parameters

trx	in: transaction
parent	in: parent node, i.e., a thr node

UNIV_INTERN ibool row_undo_search_clust_to_pcur

(

undo_node_t *

node

)

Looks for the clustered index record when node has the row reference. The pcur in node is used in the search. If found, stores the row to node, and stores the position of pcur, and detaches it. The pcur must be closed by the caller in any case.

Returns

TRUE if found; NOTE the node->pcur must be closed by the caller, regardless of the return value in: row undo node

UNIV_INTERN que_thr_t* row_undo_step

(

que_thr_t *

thr

)

Undoes a row operation in a table. This is a high-level function used in SQL execution graphs.

Returns

query thread to run next or NULL in: query thread