The index tree cursor. More...

#include <stddef.h>
#include <sys/types.h>
#include "btr0types.h"
#include "dict0dict.h"
#include "gis0type.h"
#include "page0cur.h"
#include "univ.i"
#include "ha0ha.h"
#include "que0types.h"
#include "row0types.h"
#include "btr0cur.ic"

Classes
struct	btr_latch_leaves_t

struct	btr_path_t
	A slot in the path array. More...

struct	btr_cur_t
	The tree cursor: the definition appears here only for the compiler to know struct size! More...

Macros
#define	BTR_CUR_PAGE_COMPRESS_LIMIT(index) ((UNIV_PAGE_SIZE * (ulint)((index)->merge_threshold)) / 100)
	In the pessimistic delete, if the page data size drops below this limit, merging it to a neighbor is tried. More...

Enumerations
enum	{ BTR_NO_UNDO_LOG_FLAG = 1 , BTR_NO_LOCKING_FLAG = 2 , BTR_KEEP_SYS_FLAG = 4 , BTR_KEEP_POS_FLAG = 8 , BTR_CREATE_FLAG = 16 , BTR_KEEP_IBUF_BITMAP = 32 }
	Mode flags for btr_cur operations; these can be ORed. More...

enum	btr_cur_method { BTR_CUR_UNSET = 0 , BTR_CUR_HASH = 1 , BTR_CUR_HASH_NOT_ATTEMPTED , BTR_CUR_HASH_FAIL , BTR_CUR_BINARY , BTR_CUR_INSERT_TO_IBUF , BTR_CUR_DEL_MARK_IBUF , BTR_CUR_DELETE_IBUF , BTR_CUR_DELETE_REF }
	Values for the flag documenting the used search method. More...

Functions
static page_cur_t *	btr_cur_get_page_cur (const btr_cur_t *cursor)
	Returns the page cursor component of a tree cursor. More...

static buf_block_t *	btr_cur_get_block (const btr_cur_t *cursor)
	Returns the buffer block on which the tree cursor is positioned. More...

static rec_t *	btr_cur_get_rec (const btr_cur_t *cursor)
	Returns the record pointer of a tree cursor. More...

static page_zip_des_t *	btr_cur_get_page_zip (btr_cur_t *cursor)
	Returns the compressed page on which the tree cursor is positioned. More...

static page_t *	btr_cur_get_page (btr_cur_t *cursor)
	Returns the page of a tree cursor. More...

static void	btr_cur_position (dict_index_t index, rec_t rec, buf_block_t block, btr_cur_t cursor)
	Positions a tree cursor at a given record. More...

bool	btr_cur_optimistic_latch_leaves (buf_block_t block, uint64_t modify_clock, ulint latch_mode, btr_cur_t cursor, const char file, ulint line, mtr_t *mtr)
	Optimistically latches the leaf page or pages requested. More...

void	btr_cur_search_to_nth_level (dict_index_t index, ulint level, const dtuple_t tuple, page_cur_mode_t mode, ulint latch_mode, btr_cur_t cursor, ulint has_search_latch, const char file, ulint line, mtr_t *mtr)
	Searches an index tree and positions a tree cursor on a given level. More...

void	btr_cur_search_to_nth_level_with_no_latch (dict_index_t index, ulint level, const dtuple_t tuple, page_cur_mode_t mode, btr_cur_t cursor, const char file, ulint line, mtr_t *mtr, bool mark_dirty=true)
	Searches an index tree and positions a tree cursor on a given level. More...

void	btr_cur_open_at_index_side (bool from_left, dict_index_t index, ulint latch_mode, btr_cur_t cursor, ulint level, ut::Location location, mtr_t *mtr)
	Opens a cursor at either end of an index. More...

void	btr_cur_open_at_index_side_with_no_latch (bool from_left, dict_index_t index, btr_cur_t cursor, ulint level, ut::Location location, mtr_t *mtr)
	Opens a cursor at either end of an index. More...

bool	btr_cur_open_at_rnd_pos (dict_index_t index, ulint latch_mode, btr_cur_t cursor, const char file, ulint line, mtr_t mtr)
	Positions a cursor at a randomly chosen position within a B-tree. More...

dberr_t	btr_cur_optimistic_insert (ulint flags, btr_cur_t cursor, ulint offsets, mem_heap_t heap, dtuple_t entry, rec_t rec, big_rec_t big_rec, que_thr_t thr, mtr_t mtr)
	Tries to perform an insert to a page in an index tree, next to cursor. More...

dberr_t	btr_cur_pessimistic_insert (uint32_t flags, btr_cur_t cursor, ulint offsets, mem_heap_t heap, dtuple_t entry, rec_t rec, big_rec_t big_rec, que_thr_t thr, mtr_t mtr)
	Performs an insert on a page of an index tree. More...

bool	btr_cur_update_alloc_zip_func (page_zip_des_t page_zip, page_cur_t cursor, dict_index_t index, ulint offsets, ulint length, bool create, mtr_t *mtr)
	See if there is enough place in the page modification log to log an update-in-place. More...

bool	btr_cur_update_alloc_zip (page_zip_des_t page_zip, page_cur_t cursor, dict_index_t index, ulint offsets, ulint len, bool cr, mtr_t *mtr)

dberr_t	btr_cur_update_in_place (ulint flags, btr_cur_t cursor, ulint offsets, const upd_t update, ulint cmpl_info, que_thr_t thr, trx_id_t trx_id, mtr_t *mtr)
	Updates a record when the update causes no size changes in its fields. More...

void	btr_cur_update_in_place_log (ulint flags, const rec_t rec, dict_index_t index, const upd_t update, trx_id_t trx_id, roll_ptr_t roll_ptr, mtr_t mtr)
	Writes a redo log record of updating a record in-place. More...

dberr_t	btr_cur_optimistic_update (ulint flags, btr_cur_t cursor, ulint offsets, mem_heap_t heap, const upd_t update, ulint cmpl_info, que_thr_t thr, trx_id_t trx_id, mtr_t mtr)
	Tries to update a record on a page in an index tree. More...

dberr_t	btr_cur_pessimistic_update (ulint flags, btr_cur_t cursor, ulint offsets, mem_heap_t offsets_heap, mem_heap_t entry_heap, big_rec_t *big_rec, upd_t update, ulint cmpl_info, que_thr_t thr, trx_id_t trx_id, undo_no_t undo_no, mtr_t mtr, btr_pcur_t *pcur=nullptr)
	Performs an update of a record on a page of a tree. More...

dberr_t	btr_cur_del_mark_set_clust_rec (ulint flags, buf_block_t block, rec_t rec, dict_index_t index, const ulint offsets, que_thr_t thr, const dtuple_t entry, mtr_t *mtr)
	Marks a clustered index record deleted. More...

dberr_t	btr_cur_del_mark_set_sec_rec (ulint flags, btr_cur_t cursor, bool val, que_thr_t thr, mtr_t *mtr)
	Sets a secondary index record delete mark to true or false. More...

bool	btr_cur_compress_if_useful (btr_cur_t cursor, bool adjust, mtr_t mtr)
	Tries to compress a page of the tree if it seems useful. More...

bool	btr_cur_optimistic_delete_func (btr_cur_t cursor, ulint flags, mtr_t mtr)

bool	btr_cur_optimistic_delete (btr_cur_t cursor, ulint flags, mtr_t mtr)
	Removes the record on which the tree cursor is positioned on a leaf page. More...

bool	btr_cur_pessimistic_delete (dberr_t err, bool has_reserved_extents, btr_cur_t cursor, uint32_t flags, bool rollback, trx_id_t trx_id, undo_no_t undo_no, ulint rec_type, mtr_t mtr, btr_pcur_t pcur, purge_node_t *node)
	Removes the record on which the tree cursor is positioned. More...

const byte *	btr_cur_parse_update_in_place (const byte ptr, const byte end_ptr, page_t page, page_zip_des_t page_zip, dict_index_t *index)
	Parses a redo log record of updating a record in-place. More...

const byte *	btr_cur_parse_del_mark_set_clust_rec (const byte ptr, const byte end_ptr, page_t page, page_zip_des_t page_zip, dict_index_t *index)
	Parses the redo log record for delete marking or unmarking of a clustered index record. More...

const byte *	btr_cur_parse_del_mark_set_sec_rec (const byte ptr, const byte end_ptr, page_t page, page_zip_des_t page_zip)
	Parses the redo log record for delete marking or unmarking of a secondary index record. More...

int64_t	btr_estimate_n_rows_in_range (dict_index_t index, const dtuple_t tuple1, page_cur_mode_t mode1, const dtuple_t *tuple2, page_cur_mode_t mode2)
	Estimates the number of rows in a given index range. More...

bool	btr_estimate_number_of_different_key_vals (dict_index_t *index)
	Estimates the number of different key values in a given index, for each n-column prefix of the index where 1 <= n <= dict_index_get_n_unique(index). More...

byte *	btr_rec_copy_externally_stored_field_func (trx_t trx, dict_index_t index, const rec_t rec, const ulint offsets, const page_size_t &page_size, ulint no, ulint len, size_t lob_version, bool is_sdi, mem_heap_t *heap)
	Copies an externally stored field of a record to mem heap. More...

void	btr_cur_set_deleted_flag_for_ibuf (rec_t rec, page_zip_des_t page_zip, bool val, mtr_t *mtr)
	Sets a secondary index record's delete mark to the given value. More...

static void	btr_rec_set_deleted_flag (rec_t rec, page_zip_des_t page_zip, bool flag)
	The following function is used to set the deleted bit of a record. More...

btr_latch_leaves_t	btr_cur_latch_leaves (buf_block_t block, const page_id_t &page_id, const page_size_t &page_size, ulint latch_mode, btr_cur_t cursor, mtr_t *mtr)
	Latches the leaf page or pages requested. More...

bool	materialize_instant_default (const dict_index_t index, const rec_t rec)
	If default value of INSTANT ADD column is to be materialize in updated row. More...

Variables
constexpr uint32_t	BTR_PATH_ARRAY_N_SLOTS = 250
	size of path array (in slots) More...

constexpr uint32_t	BTR_CUR_RETRY_DELETE_N_TIMES = 100
	If pessimistic delete fails because of lack of file space, there is still a good change of success a little later. More...

constexpr uint32_t	BTR_CUR_RETRY_SLEEP_TIME_MS = 50
	If pessimistic delete fails because of lack of file space, there is still a good change of success a little later. More...

ulint	btr_cur_n_non_sea
	Number of searches down the B-tree in btr_cur_search_to_nth_level(). More...

ulint	btr_cur_n_sea
	Number of successful adaptive hash index lookups in btr_cur_search_to_nth_level(). More...

ulint	btr_cur_n_non_sea_old
	Old value of btr_cur_n_non_sea. More...

ulint	btr_cur_n_sea_old
	Old value of btr_cur_n_sea. More...

uint	btr_cur_limit_optimistic_insert_debug

Detailed Description

The index tree cursor.

Created 10/16/1994 Heikki Tuuri

Macro Definition Documentation

◆ BTR_CUR_PAGE_COMPRESS_LIMIT

#define BTR_CUR_PAGE_COMPRESS_LIMIT ( index ) ((UNIV_PAGE_SIZE * (ulint)((index)->merge_threshold)) / 100)

In the pessimistic delete, if the page data size drops below this limit, merging it to a neighbor is tried.

Enumeration Type Documentation

◆ anonymous enum

anonymous enum

Mode flags for btr_cur operations; these can be ORed.

Enumerator
BTR_NO_UNDO_LOG_FLAG	do no undo logging
BTR_NO_LOCKING_FLAG	do no record lock checking
BTR_KEEP_SYS_FLAG	sys fields will be found in the update vector or inserted entry
BTR_KEEP_POS_FLAG	btr_cur_pessimistic_update() must keep cursor position when moving columns to big_rec
BTR_CREATE_FLAG	the caller is creating the index or wants to bypass the index->info.online creation log
BTR_KEEP_IBUF_BITMAP	the caller of btr_cur_optimistic_update() or btr_cur_update_in_place() will take care of updating IBUF_BITMAP_FREE

◆ btr_cur_method

enum btr_cur_method

Values for the flag documenting the used search method.

Enumerator
BTR_CUR_UNSET	Flag for initialization only, not in real use.
BTR_CUR_HASH	successful shortcut using the hash index
BTR_CUR_HASH_NOT_ATTEMPTED	a search using hash index was not performed.
BTR_CUR_HASH_FAIL	failure using hash, success using binary search. The record pointing by the cursor may need to be updated in AHI.
BTR_CUR_BINARY	success using the binary search
BTR_CUR_INSERT_TO_IBUF	performed the intended insert to the insert buffer
BTR_CUR_DEL_MARK_IBUF	performed the intended delete mark in the insert/delete buffer
BTR_CUR_DELETE_IBUF	performed the intended delete in the insert/delete buffer
BTR_CUR_DELETE_REF	row_purge_poss_sec() failed

Function Documentation

◆ btr_cur_compress_if_useful()

bool btr_cur_compress_if_useful	(	btr_cur_t *	cursor,
		bool	adjust,
		mtr_t *	mtr
	)

Tries to compress a page of the tree if it seems useful.

It is assumed that mtr holds an x-latch on the tree and on the cursor page. To avoid deadlocks, mtr must also own x-latches to brothers of page, if those brothers exist. NOTE: it is assumed that the caller has reserved enough free extents so that the compression will always succeed if done!

Returns: true if compression occurred in/out: mini-transaction

It is assumed that mtr holds an x-latch on the tree and on the cursor page. To avoid deadlocks, mtr must also own x-latches to brothers of page, if those brothers exist. NOTE: it is assumed that the caller has reserved enough free extents so that the compression will always succeed if done!

Returns: true if compression occurred

Parameters

cursor	in/out: cursor on the page to compress; cursor does not stay valid if !adjust and compression occurs
adjust	in: true if should adjust the cursor position even if compression occurs
mtr	in/out: mini-transaction

◆ btr_cur_del_mark_set_clust_rec()

dberr_t btr_cur_del_mark_set_clust_rec	(	ulint	flags,
		buf_block_t *	block,
		rec_t *	rec,
		dict_index_t *	index,
		const ulint *	offsets,
		que_thr_t *	thr,
		const dtuple_t *	entry,
		mtr_t *	mtr
	)

Marks a clustered index record deleted.

Writes an undo log record to undo log on this delete marking. Writes in the trx id field the id of the deleting transaction, and in the roll ptr field pointer to the undo log record created.

Returns: DB_SUCCESS, DB_LOCK_WAIT, or error number in/out: mini-transaction

Writes an undo log record to undo log on this delete marking. Writes in the trx id field the id of the deleting transaction, and in the roll ptr field pointer to the undo log record created.

Returns: DB_SUCCESS, DB_LOCK_WAIT, or error number

Parameters

flags	in: undo logging and locking flags
block	in/out: buffer block of the record
rec	in/out: record
index	in: clustered index of the record
offsets	in: rec_get_offsets(rec)
thr	in: query thread
entry	in: dtuple for the deleting record, also contains the virtual cols if there are any
mtr	in/out: mini-transaction

◆ btr_cur_del_mark_set_sec_rec()

dberr_t btr_cur_del_mark_set_sec_rec	(	ulint	flags,
		btr_cur_t *	cursor,
		bool	val,
		que_thr_t *	thr,
		mtr_t *	mtr
	)

Sets a secondary index record delete mark to true or false.

Returns: DB_SUCCESS, DB_LOCK_WAIT, or error number in/out: mini-transaction; DB_SUCCESS, DB_LOCK_WAIT, or error number

Parameters

flags	in: locking flag
cursor	in: cursor
val	in: value to set
thr	in: query thread
mtr	in/out: mini-transaction

◆ btr_cur_get_block()

static buf_block_t * btr_cur_get_block ( const btr_cur_t * cursor )

inlinestatic

Returns the buffer block on which the tree cursor is positioned.

Returns: pointer to buffer block in: tree cursor

◆ btr_cur_get_page()

static page_t * btr_cur_get_page ( btr_cur_t * cursor )

inlinestatic

Returns the page of a tree cursor.

Returns: pointer to page in: tree cursor

◆ btr_cur_get_page_cur()

static page_cur_t * btr_cur_get_page_cur ( const btr_cur_t * cursor )

inlinestatic

Returns the page cursor component of a tree cursor.

Returns: pointer to page cursor component in: tree cursor

◆ btr_cur_get_page_zip()

static page_zip_des_t * btr_cur_get_page_zip ( btr_cur_t * cursor )

inlinestatic

Returns the compressed page on which the tree cursor is positioned.

Returns: pointer to compressed page, or NULL if the page is not compressed in: tree cursor

◆ btr_cur_get_rec()

static rec_t * btr_cur_get_rec ( const btr_cur_t * cursor )

inlinestatic

Returns the record pointer of a tree cursor.

Returns: pointer to record in: tree cursor

◆ btr_cur_latch_leaves()

btr_latch_leaves_t btr_cur_latch_leaves	(	buf_block_t *	block,
		const page_id_t &	page_id,
		const page_size_t &	page_size,
		ulint	latch_mode,
		btr_cur_t *	cursor,
		mtr_t *	mtr
	)

Latches the leaf page or pages requested.

Parameters

[in]	block	Leaf page where the search converged
[in]	page_id	Page id of the leaf
[in]	page_size	Page size
[in]	latch_mode	BTR_SEARCH_LEAF, ...
[in]	cursor	Cursor
[in]	mtr	Mini-transaction

Returns: blocks and savepoints which actually latched.

◆ btr_cur_open_at_index_side()

void btr_cur_open_at_index_side	(	bool	from_left,
		dict_index_t *	index,
		ulint	latch_mode,
		btr_cur_t *	cursor,
		ulint	level,
		ut::Location	location,
		mtr_t *	mtr
	)

Opens a cursor at either end of an index.

Parameters

[in]	from_left	True if open to the low end, false if to the high end
[in]	index	Index
[in]	latch_mode	Latch mode
[in,out]	cursor	Cursor
[in]	level	Level to search for (0=leaf)
[in]	location	Location where called
[in,out]	mtr	Mini-transaction

◆ btr_cur_open_at_index_side_with_no_latch()

void btr_cur_open_at_index_side_with_no_latch	(	bool	from_left,
		dict_index_t *	index,
		btr_cur_t *	cursor,
		ulint	level,
		ut::Location	location,
		mtr_t *	mtr
	)

Opens a cursor at either end of an index.

Avoid taking latches on buffer, just pin (by incrementing fix_count) to keep them in buffer pool. This mode is used by intrinsic table as they are not shared and so there is no need of latching.

Parameters

[in]	from_left	true if open to low end, false if open to high end.
[in]	index	Index
[in,out]	cursor	Cursor
[in]	level	Level to search for (0=leaf)
[in]	location	Location where called
[in,out]	mtr	Mini-transaction

◆ btr_cur_open_at_rnd_pos()

bool btr_cur_open_at_rnd_pos	(	dict_index_t *	index,
		ulint	latch_mode,
		btr_cur_t *	cursor,
		const char *	file,
		ulint	line,
		mtr_t *	mtr
	)

Positions a cursor at a randomly chosen position within a B-tree.

Returns: true if the index is available and we have put the cursor, false if the index is unavailable in: mtr; true if the index is available and we have put the cursor, false if the index is unavailable

Parameters

index	in: index
latch_mode	in: BTR_SEARCH_LEAF, ...
cursor	in/out: B-tree cursor
file	in: file name
line	in: line where called
mtr	in: mtr

◆ btr_cur_optimistic_delete()

bool btr_cur_optimistic_delete	(	btr_cur_t *	cursor,
		ulint	flags,
		mtr_t *	mtr
	)

inline

Removes the record on which the tree cursor is positioned on a leaf page.

It is assumed that the mtr has an x-latch on the page where the cursor is positioned, but no latch on the whole tree.

Parameters

[in]	cursor	cursor on leaf page, on the record to delete; cursor stays valid: if deletion succeeds, on function exit it points to the successor of the deleted record
[in]	flags	BTR_CREATE_FLAG or 0
[in]	mtr	if this function returns true on a leaf page of a secondary index, the mtr must be committed before latching any further pages

Returns: true if success, i.e., the page did not become too empty

◆ btr_cur_optimistic_delete_func()

bool btr_cur_optimistic_delete_func	(	btr_cur_t *	cursor,
		ulint	flags,
		mtr_t *	mtr
	)

◆ btr_cur_optimistic_insert()

dberr_t btr_cur_optimistic_insert	(	ulint	flags,
		btr_cur_t *	cursor,
		ulint **	offsets,
		mem_heap_t **	heap,
		dtuple_t *	entry,
		rec_t **	rec,
		big_rec_t **	big_rec,
		que_thr_t *	thr,
		mtr_t *	mtr
	)

Tries to perform an insert to a page in an index tree, next to cursor.

It is assumed that mtr holds an x-latch on the page. The operation does not succeed if there is too little space on the page. If there is just one record on the page, the insert will always succeed; this is to prevent trying to split a page with just one record.

Returns: DB_SUCCESS, DB_WAIT_LOCK, DB_FAIL, or error number in/out: mini-transaction; if this function returns DB_SUCCESS on a leaf page of a secondary index in a compressed tablespace, the caller must mtr_commit(mtr) before latching any further pages

It is assumed that mtr holds an x-latch on the page. The operation does not succeed if there is too little space on the page. If there is just one record on the page, the insert will always succeed; this is to prevent trying to split a page with just one record.

Returns: DB_SUCCESS, DB_WAIT_LOCK, DB_FAIL, or error number

Parameters

flags	in: undo logging and locking flags: if not zero, the parameters index and thr should be specified
cursor	in: cursor on page after which to insert; cursor stays valid
offsets	out: offsets on *rec
heap	in/out: pointer to memory heap, or NULL
entry	in/out: entry to insert
rec	out: pointer to inserted record if succeed
big_rec	out: big rec vector whose fields have to be stored externally by the caller, or NULL
thr	in: query thread or NULL
mtr	in/out: mini-transaction; if this function returns DB_SUCCESS on a leaf page of a secondary index in a compressed tablespace, the caller must mtr_commit(mtr) before latching any further pages

◆ btr_cur_optimistic_latch_leaves()

bool btr_cur_optimistic_latch_leaves	(	buf_block_t *	block,
		uint64_t	modify_clock,
		ulint *	latch_mode,
		btr_cur_t *	cursor,
		const char *	file,
		ulint	line,
		mtr_t *	mtr
	)

Optimistically latches the leaf page or pages requested.

Parameters

[in]	block	Guessed buffer block
[in]	modify_clock	Modify clock value
[in,out]	latch_mode	BTR_SEARCH_LEAF, ...
[in,out]	cursor	Cursor
[in]	file	File name
[in]	line	Line where called
[in]	mtr	Mini-transaction

Returns: true if success

◆ btr_cur_optimistic_update()

dberr_t btr_cur_optimistic_update	(	ulint	flags,
		btr_cur_t *	cursor,
		ulint **	offsets,
		mem_heap_t **	heap,
		const upd_t *	update,
		ulint	cmpl_info,
		que_thr_t *	thr,
		trx_id_t	trx_id,
		mtr_t *	mtr
	)

Tries to update a record on a page in an index tree.

It is assumed that mtr holds an x-latch on the page. The operation does not succeed if there is too little space on the page or if the update would result in too empty a page, so that tree compression is recommended. We assume here that the ordering fields of the record do not change.

Parameters

[in]	flags	undo logging and locking flags
[in]	cursor	cursor on the record to update; cursor stays valid and positioned on the same record
[out]	offsets	offsets on cursor->page_cur.rec
[in,out]	heap	pointer to nullptr or memory heap
[in]	update	update vector; this must also contain trx id and roll ptr fields
[in]	cmpl_info	compiler info on secondary index updates
[in]	thr	query thread, or nullptr if flags & (BTR_NO_UNDO_LOG_FLAG \| BTR_NO_LOCKING_FLAG \| BTR_CREATE_FLAG \| BTR_KEEP_SYS_FLAG)
[in]	trx_id	transaction id
[in,out]	mtr	mini-transaction; if this is a secondary index, the caller must mtr_commit(mtr) before latching any further pages

Returns: error code, including

Return values

DB_SUCCESS	on success
DB_OVERFLOW	if the updated record does not fit
DB_UNDERFLOW	if the page would become too empty
DB_ZIP_OVERFLOW	if there is not enough space left on the compressed page (IBUF_BITMAP_FREE was reset outside mtr)

◆ btr_cur_parse_del_mark_set_clust_rec()

const byte * btr_cur_parse_del_mark_set_clust_rec	(	const byte *	ptr,
		const byte *	end_ptr,
		page_t *	page,
		page_zip_des_t *	page_zip,
		dict_index_t *	index
	)

Parses the redo log record for delete marking or unmarking of a clustered index record.

Returns: end of log record or NULL in: index corresponding to page; end of log record or NULL

Parameters

ptr	in: buffer
end_ptr	in: buffer end
page	in/out: page or NULL
page_zip	in/out: compressed page, or NULL
index	in: index corresponding to page

◆ btr_cur_parse_del_mark_set_sec_rec()

const byte * btr_cur_parse_del_mark_set_sec_rec	(	const byte *	ptr,
		const byte *	end_ptr,
		page_t *	page,
		page_zip_des_t *	page_zip
	)

Parses the redo log record for delete marking or unmarking of a secondary index record.

Returns: end of log record or NULL in/out: compressed page, or NULL; end of log record or NULL

Parameters

ptr	in: buffer
end_ptr	in: buffer end
page	in/out: page or NULL
page_zip	in/out: compressed page, or NULL

◆ btr_cur_parse_update_in_place()

const byte * btr_cur_parse_update_in_place	(	const byte *	ptr,
		const byte *	end_ptr,
		page_t *	page,
		page_zip_des_t *	page_zip,
		dict_index_t *	index
	)

Parses a redo log record of updating a record in-place.

Returns: end of log record or NULL in: index corresponding to page; end of log record or NULL

Parameters

ptr	in: buffer
end_ptr	in: buffer end
page	in/out: page or NULL
page_zip	in/out: compressed page, or NULL
index	in: index corresponding to page

◆ btr_cur_pessimistic_delete()

bool btr_cur_pessimistic_delete	(	dberr_t *	err,
		bool	has_reserved_extents,
		btr_cur_t *	cursor,
		uint32_t	flags,
		bool	rollback,
		trx_id_t	trx_id,
		undo_no_t	undo_no,
		ulint	rec_type,
		mtr_t *	mtr,
		btr_pcur_t *	pcur,
		purge_node_t *	node
	)

Removes the record on which the tree cursor is positioned.

Tries to compress the page if its fillfactor drops below a threshold or if it is the only page on the level. It is assumed that mtr holds an x-latch on the tree and on the cursor page. To avoid deadlocks, mtr must also own x-latches to brothers of page, if those brothers exist.

Parameters

[out]	err	DB_SUCCESS or DB_OUT_OF_FILE_SPACE; the latter may occur because we may have to update node pointers on upper levels, and in the case of variable length keys these may actually grow in size
[in]	has_reserved_extents	true if the caller has already reserved enough free extents so that he knows that the operation will succeed
[in]	cursor	Cursor on the record to delete; if compression does not occur, the cursor stays valid: it points to successor of deleted record on function exit
[in]	flags	BTR_CREATE_FLAG or 0
[in]	rollback	True if performing rollback, false otherwise.
[in]	trx_id	The current transaction id.
[in]	undo_no	Undo number of the transaction. This is needed for rollback to savepoint of partially updated LOB.
[in]	rec_type	Undo record type.
[in]	mtr	The mini transaction
[in]	pcur	Persistent cursor on the record to delete.
[in,out]	node	purge node or nullptr

Returns: true if compression occurred

◆ btr_cur_pessimistic_insert()

dberr_t btr_cur_pessimistic_insert	(	uint32_t	flags,
		btr_cur_t *	cursor,
		ulint **	offsets,
		mem_heap_t **	heap,
		dtuple_t *	entry,
		rec_t **	rec,
		big_rec_t **	big_rec,
		que_thr_t *	thr,
		mtr_t *	mtr
	)

Performs an insert on a page of an index tree.

It is assumed that mtr holds an x-latch on the tree and on the cursor page. If the insert is made on the leaf level, to avoid deadlocks, mtr must also own x-latches to brothers of page, if those brothers exist.

Returns: DB_SUCCESS or error number in/out: mini-transaction

It is assumed that mtr holds an x-latch on the tree and on the cursor page. If the insert is made on the leaf level, to avoid deadlocks, mtr must also own x-latches to brothers of page, if those brothers exist.

Returns: DB_SUCCESS or error number

Parameters

flags	in: undo logging and locking flags: if not zero, the parameter thr should be specified; if no undo logging is specified, then the caller must have reserved enough free extents in the file space so that the insertion will certainly succeed
cursor	in: cursor after which to insert; cursor stays valid
offsets	out: offsets on *rec
heap	in/out: pointer to memory heap that can be emptied, or NULL
entry	in/out: entry to insert
rec	out: pointer to inserted record if succeed
big_rec	out: big rec vector whose fields have to be stored externally by the caller, or NULL
thr	in: query thread or NULL
mtr	in/out: mini-transaction

◆ btr_cur_pessimistic_update()

dberr_t btr_cur_pessimistic_update	(	ulint	flags,
		btr_cur_t *	cursor,
		ulint **	offsets,
		mem_heap_t **	offsets_heap,
		mem_heap_t *	entry_heap,
		big_rec_t **	big_rec,
		upd_t *	update,
		ulint	cmpl_info,
		que_thr_t *	thr,
		trx_id_t	trx_id,
		undo_no_t	undo_no,
		mtr_t *	mtr,
		btr_pcur_t *	pcur = `nullptr`
	)

Performs an update of a record on a page of a tree.

It is assumed that mtr holds an x-latch on the tree and on the cursor page. If the update is made on the leaf level, to avoid deadlocks, mtr must also own x-latches to brothers of page, if those brothers exist.

Parameters

[in]	flags	Undo logging, locking, and rollback flags
[in,out]	cursor	cursor on the record to update; cursor may become invalid if *big_rec == NULL \|\| !(flags & BTR_KEEP_POS_FLAG)
[out]	offsets	Offsets on cursor->page_cur.rec
[in,out]	offsets_heap	Pointer to memory heap that can be emptied, or NULL
[in,out]	entry_heap	Memory heap for allocating big_rec and the index tuple.
[out]	big_rec	Big rec vector whose fields have to be stored externally by the caller, or NULL
[in,out]	update	Update vector; this is allowed to also contain trx id and roll ptr fields. Non-updated columns that are moved offpage will be appended to this.
[in]	cmpl_info	Compiler info on secondary index updates
[in]	thr	Query thread, or NULL if flags & (BTR_NO_UNDO_LOG_FLAG \| BTR_NO_LOCKING_FLAG \| BTR_CREATE_FLAG \| BTR_KEEP_SYS_FLAG)
[in]	trx_id	Transaction id
[in]	undo_no	Undo number of the transaction. This is needed for rollback to savepoint of partially updated LOB.
[in,out]	mtr	Mini-transaction; must be committed before latching any further pages
[in]	pcur	The persistent cursor on the record to update.

Returns: DB_SUCCESS or error code

◆ btr_cur_position()

static void btr_cur_position	(	dict_index_t *	index,
		rec_t *	rec,
		buf_block_t *	block,
		btr_cur_t *	cursor
	)

inlinestatic

Positions a tree cursor at a given record.

Parameters

[in]	index	index
[in]	rec	record in tree
[in]	block	buffer block of rec
[in]	cursor	cursor

◆ btr_cur_search_to_nth_level()

void btr_cur_search_to_nth_level	(	dict_index_t *	index,
		ulint	level,
		const dtuple_t *	tuple,
		page_cur_mode_t	mode,
		ulint	latch_mode,
		btr_cur_t *	cursor,
		ulint	has_search_latch,
		const char *	file,
		ulint	line,
		mtr_t *	mtr
	)

Searches an index tree and positions a tree cursor on a given level.

NOTE: n_fields_cmp in tuple must be set so that it cannot be compared to node pointer page number fields on the upper levels of the tree! Note that if mode is PAGE_CUR_LE, which is used in inserts, then cursor->up_match and cursor->low_match both will have sensible values. If mode is PAGE_CUR_GE, then up_match will a have a sensible value. in: mtr

NOTE: n_fields_cmp in tuple must be set so that it cannot be compared to node pointer page number fields on the upper levels of the tree! Note that if mode is PAGE_CUR_LE, which is used in inserts, then cursor->up_match and cursor->low_match both will have sensible values. If mode is PAGE_CUR_GE, then up_match will a have a sensible value.

If mode is PAGE_CUR_LE , cursor is left at the place where an insert of the search tuple should be performed in the B-tree. InnoDB does an insert immediately after the cursor. Thus, the cursor may end up on a user record, or on a page infimum record.

Parameters

index	in: index
level	in: the tree level of search
tuple	in: data tuple; NOTE: n_fields_cmp in tuple must be set so that it cannot get compared to the node ptr page number field!
mode	in: PAGE_CUR_L, ...; Inserts should always be made using PAGE_CUR_LE to search the position!
latch_mode	in: BTR_SEARCH_LEAF, ..., ORed with at most one of BTR_INSERT, BTR_DELETE_MARK, BTR_DELETE, or BTR_ESTIMATE; cursor->left_block is used to store a pointer to the left neighbor page, in the cases BTR_SEARCH_PREV and BTR_MODIFY_PREV; NOTE that if has_search_latch is != 0, we maybe do not have a latch set on the cursor page, we assume the caller uses his search latch to protect the record!
cursor	in/out: tree cursor; the cursor page is s- or x-latched, but see also above!
has_search_latch	in: info on the latch mode the caller currently has on search system: RW_S_LATCH, or 0
file	in: file name
line	in: line where called
mtr	in: mtr

◆ btr_cur_search_to_nth_level_with_no_latch()

void btr_cur_search_to_nth_level_with_no_latch	(	dict_index_t *	index,
		ulint	level,
		const dtuple_t *	tuple,
		page_cur_mode_t	mode,
		btr_cur_t *	cursor,
		const char *	file,
		ulint	line,
		mtr_t *	mtr,
		bool	mark_dirty
	)

Searches an index tree and positions a tree cursor on a given level.

This function will avoid placing latches while traversing the path and so should be used only for cases where-in latching is not needed.

Parameters

[in]	index	Index
[in]	level	The tree level of search
[in]	tuple	Data tuple; Note: n_fields_cmp in compared to the node ptr page node field
[in]	mode	PAGE_CUR_L, .... Insert should always be made using PAGE_CUR_LE to search the position.
[in,out]	cursor	Tree cursor; points to record of interest.
[in]	file	File name
[in]	line	Line where called from
[in,out]	mtr	Mini-transaction
[in]	mark_dirty	if true then mark the block as dirty

◆ btr_cur_set_deleted_flag_for_ibuf()

void btr_cur_set_deleted_flag_for_ibuf	(	rec_t *	rec,
		page_zip_des_t *	page_zip,
		bool	val,
		mtr_t *	mtr
	)

Sets a secondary index record's delete mark to the given value.

This function is only used by the insert buffer merge mechanism. in/out: mini-transaction

This function is only used by the insert buffer merge mechanism.

Parameters

rec	in/out: record
page_zip	in/out: compressed page corresponding to rec, or NULL when the tablespace is uncompressed
val	in: value to set
mtr	in/out: mini-transaction

◆ btr_cur_update_alloc_zip()

bool btr_cur_update_alloc_zip	(	page_zip_des_t *	page_zip,
		page_cur_t *	cursor,
		dict_index_t *	index,
		ulint *	offsets,
		ulint	len,
		bool	cr,
		mtr_t *	mtr
	)

inline

◆ btr_cur_update_alloc_zip_func()

bool btr_cur_update_alloc_zip_func	(	page_zip_des_t *	page_zip,
		page_cur_t *	cursor,
		dict_index_t *	index,
		ulint *	offsets,
		ulint	length,
		bool	create,
		mtr_t *	mtr
	)

See if there is enough place in the page modification log to log an update-in-place.

Parameters

[in,out]	page_zip	Compressed page.
[in,out]	cursor	B-tree page cursor.
[in]	index	The index corresponding to cursor.
[in,out]	offsets	Offsets of the cursor record.
[in]	length	size needed
[in]	create	true=delete-and-insert, false=update-in-place
[in,out]	mtr	Mini-transaction.

Return values

false	if out of space; IBUF_BITMAP_FREE will be reset outside mtr if the page was re-compressed
true	if enough place;

IMPORTANT: The caller will have to update IBUF_BITMAP_FREE if this is a secondary index leaf page. This has to be done either within the same mini-transaction, or by invoking ibuf_reset_free_bits() before mtr_commit(mtr).

◆ btr_cur_update_in_place()

dberr_t btr_cur_update_in_place	(	ulint	flags,
		btr_cur_t *	cursor,
		ulint *	offsets,
		const upd_t *	update,
		ulint	cmpl_info,
		que_thr_t *	thr,
		trx_id_t	trx_id,
		mtr_t *	mtr
	)

Updates a record when the update causes no size changes in its fields.

Parameters

[in]	flags	Undo logging and locking flags
[in]	cursor	Cursor on the record to update; cursor stays valid and positioned on the same record
[in,out]	offsets	Offsets on cursor->page_cur.rec
[in]	update	Update vector
[in]	cmpl_info	Compiler info on secondary index updates
[in]	thr	Query thread, or null if flags & (btr_no_locking_flag \| btr_no_undo_log_flag \| btr_create_flag \| btr_keep_sys_flag)
[in]	trx_id	Transaction id
[in,out]	mtr	Mini-transaction; if this is a secondary index, the caller must mtr_commit(mtr) before latching any further pages

Returns: locking or undo log related error code, or

Return values

DB_SUCCESS	on success
DB_ZIP_OVERFLOW	if there is not enough space left on the compressed page (IBUF_BITMAP_FREE was reset outside mtr)

◆ btr_cur_update_in_place_log()

void btr_cur_update_in_place_log	(	ulint	flags,
		const rec_t *	rec,
		dict_index_t *	index,
		const upd_t *	update,
		trx_id_t	trx_id,
		roll_ptr_t	roll_ptr,
		mtr_t *	mtr
	)

Writes a redo log record of updating a record in-place.

Parameters

[in]	flags	Undo logging and locking flags
[in]	rec	Record
[in]	index	Index of the record
[in]	update	Update vector
[in]	trx_id	Transaction id
[in]	roll_ptr	Roll ptr
[in]	mtr	Mini-transaction

◆ btr_estimate_n_rows_in_range()

int64_t btr_estimate_n_rows_in_range	(	dict_index_t *	index,
		const dtuple_t *	tuple1,
		page_cur_mode_t	mode1,
		const dtuple_t *	tuple2,
		page_cur_mode_t	mode2
	)

Estimates the number of rows in a given index range.

Parameters

[in]	index	index
[in]	tuple1	range start, may also be empty tuple
[in]	mode1	search mode for range start
[in]	tuple2	range end, may also be empty tuple
[in]	mode2	search mode for range end

Returns: estimated number of rows

◆ btr_estimate_number_of_different_key_vals()

bool btr_estimate_number_of_different_key_vals ( dict_index_t * index )

Estimates the number of different key values in a given index, for each n-column prefix of the index where 1 <= n <= dict_index_get_n_unique(index).

The estimates are stored in the array index->stat_n_diff_key_vals[] (indexed 0..n_uniq-1) and the number of pages that were sampled is saved in index->stat_n_sample_sizes[]. If innodb_stats_method is nulls_ignored, we also record the number of non-null values for each prefix and stored the estimates in array index->stat_n_non_null_key_vals.

Returns: true if the index is available and we get the estimated numbers, false if the index is unavailable. in: index

The estimates are stored in the array index->stat_n_diff_key_vals[] (indexed 0..n_uniq-1) and the number of pages that were sampled is saved in index->stat_n_sample_sizes[]. If innodb_stats_method is nulls_ignored, we also record the number of non-null values for each prefix and stored the estimates in array index->stat_n_non_null_key_vals.

Returns: true if the index is available and we get the estimated numbers, false if the index is unavailable.

Parameters

index in: index

◆ btr_rec_copy_externally_stored_field_func()

byte * btr_rec_copy_externally_stored_field_func	(	trx_t *	trx,
		dict_index_t *	index,
		const rec_t *	rec,
		const ulint *	offsets,
		const page_size_t &	page_size,
		ulint	no,
		ulint *	len,
		size_t *	lob_version,
		bool	is_sdi,
		mem_heap_t *	heap
	)

Copies an externally stored field of a record to mem heap.

Parameters

[in]	trx	the trx doing the operation.
[in]	index	index containing the LOB.
[in]	rec	record in a clustered index; must be protected by a lock or a page latch
[in]	offsets	array returned by rec_get_offsets()
[in]	page_size	BLOB page size
[in]	no	field number
[out]	len	length of the field
[out]	lob_version	version of lob
[in]	is_sdi	true for SDI Indexes
[in,out]	heap	mem heap

Returns: the field copied to heap, or NULL if the field is incomplete

◆ btr_rec_set_deleted_flag()

static void btr_rec_set_deleted_flag	(	rec_t *	rec,
		page_zip_des_t *	page_zip,
		bool	flag
	)

inlinestatic

The following function is used to set the deleted bit of a record.

Parameters

[in,out]	rec	physical record
[in,out]	page_zip	compressed page (or NULL)
[in]	flag	nonzero if delete marked

◆ materialize_instant_default()

bool materialize_instant_default	(	const dict_index_t *	index,
		const rec_t *	rec
	)

If default value of INSTANT ADD column is to be materialize in updated row.

Parameters

[in]	index	record descriptor
[in]	rec	record

Returns: true if instant add column(s) to be materialized.

Variable Documentation

◆ btr_cur_limit_optimistic_insert_debug

uint btr_cur_limit_optimistic_insert_debug

extern

◆ btr_cur_n_non_sea

ulint btr_cur_n_non_sea

extern

Number of searches down the B-tree in btr_cur_search_to_nth_level().

◆ btr_cur_n_non_sea_old

ulint btr_cur_n_non_sea_old

extern

Old value of btr_cur_n_non_sea.

Copied by srv_refresh_innodb_monitor_stats(). Referenced by srv_printf_innodb_monitor().

◆ btr_cur_n_sea

ulint btr_cur_n_sea

extern

Number of successful adaptive hash index lookups in btr_cur_search_to_nth_level().

◆ btr_cur_n_sea_old

ulint btr_cur_n_sea_old

extern

Old value of btr_cur_n_sea.

Copied by srv_refresh_innodb_monitor_stats(). Referenced by srv_printf_innodb_monitor().

◆ BTR_CUR_RETRY_DELETE_N_TIMES

constexpr uint32_t BTR_CUR_RETRY_DELETE_N_TIMES = 100

constexpr

If pessimistic delete fails because of lack of file space, there is still a good change of success a little later.

Try this many times.

◆ BTR_CUR_RETRY_SLEEP_TIME_MS

constexpr uint32_t BTR_CUR_RETRY_SLEEP_TIME_MS = 50

constexpr

If pessimistic delete fails because of lack of file space, there is still a good change of success a little later.

Sleep this many milliseconds between retries.

◆ BTR_PATH_ARRAY_N_SLOTS

constexpr uint32_t BTR_PATH_ARRAY_N_SLOTS = 250

constexpr

size of path array (in slots)

Classes

Macros

Enumerations

Functions

Variables

Detailed Description

Macro Definition Documentation

◆ BTR_CUR_PAGE_COMPRESS_LIMIT

Enumeration Type Documentation

◆ anonymous enum

◆ btr_cur_method

Function Documentation

◆ btr_cur_compress_if_useful()

◆ btr_cur_del_mark_set_clust_rec()

◆ btr_cur_del_mark_set_sec_rec()

◆ btr_cur_get_block()

◆ btr_cur_get_page()

◆ btr_cur_get_page_cur()

◆ btr_cur_get_page_zip()

◆ btr_cur_get_rec()

◆ btr_cur_latch_leaves()

◆ btr_cur_open_at_index_side()

◆ btr_cur_open_at_index_side_with_no_latch()

◆ btr_cur_open_at_rnd_pos()

◆ btr_cur_optimistic_delete()

◆ btr_cur_optimistic_delete_func()

◆ btr_cur_optimistic_insert()

◆ btr_cur_optimistic_latch_leaves()

◆ btr_cur_optimistic_update()

◆ btr_cur_parse_del_mark_set_clust_rec()

◆ btr_cur_parse_del_mark_set_sec_rec()

◆ btr_cur_parse_update_in_place()

◆ btr_cur_pessimistic_delete()

◆ btr_cur_pessimistic_insert()

◆ btr_cur_pessimistic_update()

◆ btr_cur_position()

◆ btr_cur_search_to_nth_level()

◆ btr_cur_search_to_nth_level_with_no_latch()

◆ btr_cur_set_deleted_flag_for_ibuf()

◆ btr_cur_update_alloc_zip()

◆ btr_cur_update_alloc_zip_func()

◆ btr_cur_update_in_place()

◆ btr_cur_update_in_place_log()

◆ btr_estimate_n_rows_in_range()

◆ btr_estimate_number_of_different_key_vals()

◆ btr_rec_copy_externally_stored_field_func()

◆ btr_rec_set_deleted_flag()

◆ materialize_instant_default()

Variable Documentation

◆ btr_cur_limit_optimistic_insert_debug

◆ btr_cur_n_non_sea

◆ btr_cur_n_non_sea_old

◆ btr_cur_n_sea

◆ btr_cur_n_sea_old

◆ BTR_CUR_RETRY_DELETE_N_TIMES

◆ BTR_CUR_RETRY_SLEEP_TIME_MS

◆ BTR_PATH_ARRAY_N_SLOTS