The page cursor. More...

#include "univ.i"
#include "buf0types.h"
#include "data0data.h"
#include "gis0type.h"
#include "mtr0mtr.h"
#include "page0page.h"
#include "rem0rec.h"
#include "rem0wrec.h"
#include "page0cur.ic"

Classes
struct	page_cur_t
	Index page cursor. More...

Macros
#define	PAGE_CUR_ADAPT

Functions
static page_t *	page_cur_get_page (page_cur_t *cur)
	Gets pointer to the page frame where the cursor is positioned. More...

static buf_block_t *	page_cur_get_block (page_cur_t *cur)
	Gets pointer to the buffer block where the cursor is positioned. More...

static page_zip_des_t *	page_cur_get_page_zip (page_cur_t *cur)
	Gets pointer to the page frame where the cursor is positioned. More...

static rec_t *	page_cur_get_rec (page_cur_t *cur)
	Gets the record where the cursor is positioned. More...

static void	page_cur_set_before_first (const buf_block_t block, page_cur_t cur)
	Sets the cursor object to point before the first user record on the page. More...

static void	page_cur_set_after_last (const buf_block_t block, page_cur_t cur)
	Sets the cursor object to point after the last user record on the page. More...

static bool	page_cur_is_before_first (const page_cur_t *cur)
	Returns true if the cursor is before first user record on page. More...

static bool	page_cur_is_after_last (const page_cur_t *cur)
	Returns true if the cursor is after last user record. More...

static void	page_cur_position (const rec_t rec, const buf_block_t block, page_cur_t *cur)
	Positions the cursor on the given record. More...

static void	page_cur_move_to_next (page_cur_t *cur)
	Moves the cursor to the next record on page. More...

static void	page_cur_move_to_prev (page_cur_t *cur)
	Moves the cursor to the previous record on page. More...

static rec_t *	page_cur_tuple_insert (page_cur_t cursor, const dtuple_t tuple, dict_index_t index, ulint offsets, mem_heap_t heap, mtr_t mtr)
	Inserts a record next to page cursor. More...

static rec_t *	page_cur_rec_insert (page_cur_t cursor, const rec_t rec, dict_index_t index, ulint offsets, mtr_t *mtr)
	Inserts a record next to page cursor. More...

rec_t *	page_cur_insert_rec_low (rec_t current_rec, dict_index_t index, const rec_t rec, ulint offsets, mtr_t *mtr)
	Inserts a record next to page cursor on an uncompressed page. More...

rec_t *	page_cur_direct_insert_rec_low (rec_t current_rec, dict_index_t index, const dtuple_t tuple, mtr_t mtr, ulint rec_size)
	Inserts a record next to page cursor on an uncompressed page. More...

rec_t *	page_cur_insert_rec_zip (page_cur_t cursor, dict_index_t index, const rec_t rec, ulint offsets, mtr_t *mtr)
	Inserts a record next to page cursor on a compressed and uncompressed page. More...

void	page_copy_rec_list_end_to_created_page (page_t new_page, rec_t rec, dict_index_t index, mtr_t mtr)
	Copies records from page to a newly created page, from a given record onward, including that record. More...

void	page_cur_delete_rec (page_cur_t cursor, const dict_index_t index, const ulint offsets, mtr_t mtr)
	Deletes a record at the page cursor. More...

static ulint	page_cur_search (const buf_block_t block, const dict_index_t index, const dtuple_t tuple, page_cur_mode_t mode, page_cur_t cursor)
	Search the right position for a page cursor. More...

static ulint	page_cur_search (const buf_block_t block, const dict_index_t index, const dtuple_t tuple, page_cur_t cursor)
	Search the right position for a page cursor. More...

void	page_cur_search_with_match (const buf_block_t block, const dict_index_t index, const dtuple_t tuple, page_cur_mode_t mode, ulint iup_matched_fields, ulint ilow_matched_fields, page_cur_t cursor, rtr_info_t *rtr_info)
	Searches the right position for a page cursor. More...

void	page_cur_search_with_match_bytes (const buf_block_t block, const dict_index_t index, const dtuple_t tuple, page_cur_mode_t mode, ulint iup_matched_fields, ulint iup_matched_bytes, ulint ilow_matched_fields, ulint ilow_matched_bytes, page_cur_t cursor)
	Search the right position for a page cursor. More...

void	page_cur_open_on_rnd_user_rec (buf_block_t block, page_cur_t cursor)
	Positions a page cursor on a randomly chosen user record on a page. More...

const byte *	page_cur_parse_insert_rec (bool is_short, const byte ptr, const byte end_ptr, buf_block_t block, dict_index_t index, mtr_t *mtr)
	Parses a log record of a record insert on a page. More...

const byte *	page_parse_copy_rec_list_to_created_page (const byte ptr, const byte end_ptr, buf_block_t block, dict_index_t index, mtr_t *mtr)
	Parses a log record of copying a record list end to a new created page. More...

const byte *	page_cur_parse_delete_rec (const byte ptr, const byte end_ptr, buf_block_t block, dict_index_t index, mtr_t *mtr)
	Parses log record of a record delete on a page. More...

bool	page_delete_rec (const dict_index_t index, page_cur_t pcur, const ulint *offsets)
	Removes the record from a leaf page. More...

Detailed Description

The page cursor.

Created 10/4/1994 Heikki Tuuri

Macro Definition Documentation

◆ PAGE_CUR_ADAPT

#define PAGE_CUR_ADAPT

Function Documentation

◆ page_copy_rec_list_end_to_created_page()

void page_copy_rec_list_end_to_created_page	(	page_t *	new_page,
		rec_t *	rec,
		dict_index_t *	index,
		mtr_t *	mtr
	)

Copies records from page to a newly created page, from a given record onward, including that record.

Infimum and supremum records are not copied.

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

Infimum and supremum records are not copied.

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

Parameters

new_page	in/out: index page to copy to
rec	in: first record to copy
index	in: record descriptor
mtr	in: mtr

◆ page_cur_delete_rec()

void page_cur_delete_rec	(	page_cur_t *	cursor,
		const dict_index_t *	index,
		const ulint *	offsets,
		mtr_t *	mtr
	)

Deletes a record at the page cursor.

The cursor is moved to the next record after the deleted one. in: mini-transaction handle

The cursor is moved to the next record after the deleted one.

Parameters

cursor	in/out: a page cursor
index	in: record descriptor
offsets	in: rec_get_offsets( cursor->rec, index)
mtr	in: mini-transaction handle or NULL

◆ page_cur_direct_insert_rec_low()

rec_t * page_cur_direct_insert_rec_low	(	rec_t *	current_rec,
		dict_index_t *	index,
		const dtuple_t *	tuple,
		mtr_t *	mtr,
		ulint	rec_size
	)

Inserts a record next to page cursor on an uncompressed page.

Parameters

[in]	current_rec	Pointer to current record after which the new record is inserted.
[in]	index	Record descriptor
[in]	tuple	Pointer to a data tuple
[in]	mtr	Mini-transaction handle, or NULL
[in]	rec_size	The size of new record

Returns: pointer to record if succeed, NULL otherwise

< the relevant page

< cursor position at previous insert

< a free record that was reused, or NULL

< inserted record

< heap number of the inserted record

◆ page_cur_get_block()

static buf_block_t * page_cur_get_block ( page_cur_t * cur )

inlinestatic

Gets pointer to the buffer block where the cursor is positioned.

Returns: page in: page cursor

◆ page_cur_get_page()

static page_t * page_cur_get_page ( page_cur_t * cur )

inlinestatic

Gets pointer to the page frame where the cursor is positioned.

Returns: page in: page cursor

◆ page_cur_get_page_zip()

static page_zip_des_t * page_cur_get_page_zip ( page_cur_t * cur )

inlinestatic

Gets pointer to the page frame where the cursor is positioned.

Returns: page in: page cursor

◆ page_cur_get_rec()

static rec_t * page_cur_get_rec ( page_cur_t * cur )

inlinestatic

Gets the record where the cursor is positioned.

Returns: record in: page cursor

◆ page_cur_insert_rec_low()

rec_t * page_cur_insert_rec_low	(	rec_t *	current_rec,
		dict_index_t *	index,
		const rec_t *	rec,
		ulint *	offsets,
		mtr_t *	mtr
	)

Inserts a record next to page cursor on an uncompressed page.

Returns pointer to inserted record if succeed, i.e., enough space available, NULL otherwise. The cursor stays at the same position.

Returns: pointer to record if succeed, NULL otherwise in: mini-transaction handle, or NULL

Returns pointer to inserted record if succeed, i.e., enough space available, NULL otherwise. The cursor stays at the same position.

Returns: pointer to record if succeed, NULL otherwise

< the relevant page

< cursor position at previous insert

< a free record that was reused, or NULL

< inserted record

< heap number of the inserted record

Parameters

current_rec	in: pointer to current record after which the new record is inserted
index	in: record descriptor
rec	in: pointer to a physical record
offsets	in/out: rec_get_offsets(rec, index)
mtr	in: mini-transaction handle, or NULL

◆ page_cur_insert_rec_zip()

rec_t * page_cur_insert_rec_zip	(	page_cur_t *	cursor,
		dict_index_t *	index,
		const rec_t *	rec,
		ulint *	offsets,
		mtr_t *	mtr
	)

Inserts a record next to page cursor on a compressed and uncompressed page.

Returns pointer to inserted record if succeed, i.e., enough space available, NULL otherwise. The cursor stays at the same position.

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

Returns: pointer to record if succeed, NULL otherwise in: mini-transaction handle, or NULL

Returns pointer to inserted record if succeed, i.e., enough space available, NULL otherwise. The cursor stays at the same position.

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

Returns: pointer to record if succeed, NULL otherwise

< the relevant page

< cursor position at previous insert

< a free record that was reused, or NULL

< inserted record

< heap number of the inserted record

Parameters

cursor	in/out: page cursor
index	in: record descriptor
rec	in: pointer to a physical record
offsets	in/out: rec_get_offsets(rec, index)
mtr	in: mini-transaction handle, or NULL

◆ page_cur_is_after_last()

static bool page_cur_is_after_last ( const page_cur_t * cur )

inlinestatic

Returns true if the cursor is after last user record.

Returns: true if at end in: cursor

◆ page_cur_is_before_first()

static bool page_cur_is_before_first ( const page_cur_t * cur )

inlinestatic

Returns true if the cursor is before first user record on page.

Returns: true if at start in: cursor

◆ page_cur_move_to_next()

static void page_cur_move_to_next ( page_cur_t * cur )

inlinestatic

Moves the cursor to the next record on page.

in/out: cursor; must not be after last

◆ page_cur_move_to_prev()

static void page_cur_move_to_prev ( page_cur_t * cur )

inlinestatic

Moves the cursor to the previous record on page.

in/out: cursor; not before first

◆ page_cur_open_on_rnd_user_rec()

void page_cur_open_on_rnd_user_rec	(	buf_block_t *	block,
		page_cur_t *	cursor
	)

Positions a page cursor on a randomly chosen user record on a page.

If there are no user records, sets the cursor on the infimum record. out: page cursor

If there are no user records, sets the cursor on the infimum record.

Parameters

block	in: page
cursor	out: page cursor

◆ page_cur_parse_delete_rec()

const byte * page_cur_parse_delete_rec	(	const byte *	ptr,
		const byte *	end_ptr,
		buf_block_t *	block,
		dict_index_t *	index,
		mtr_t *	mtr
	)

Parses log record of a record delete on a page.

Returns: pointer to record end or NULL in: mtr or NULL; pointer to record end or NULL

Parameters

ptr	in: buffer
end_ptr	in: buffer end
block	in: page or NULL
index	in: record descriptor
mtr	in: mtr or NULL

◆ page_cur_parse_insert_rec()

const byte * page_cur_parse_insert_rec	(	bool	is_short,
		const byte *	ptr,
		const byte *	end_ptr,
		buf_block_t *	block,
		dict_index_t *	index,
		mtr_t *	mtr
	)

Parses a log record of a record insert on a page.

Returns: end of log record or NULL in: mtr or NULL; end of log record or NULL

Parameters

is_short	in: true if short inserts
ptr	in: buffer
end_ptr	in: buffer end
block	in: page or NULL
index	in: record descriptor
mtr	in: mtr or NULL

◆ page_cur_position()

static void page_cur_position	(	const rec_t *	rec,
		const buf_block_t *	block,
		page_cur_t *	cur
	)

inlinestatic

Positions the cursor on the given record.

Parameters

[in]	rec	record on a page
[in]	block	buffer block containing the record
[out]	cur	page cursor

◆ page_cur_rec_insert()

static rec_t * page_cur_rec_insert	(	page_cur_t *	cursor,
		const rec_t *	rec,
		dict_index_t *	index,
		ulint *	offsets,
		mtr_t *	mtr
	)

inlinestatic

Inserts a record next to page cursor.

Returns pointer to inserted record if succeed, i.e., enough space available, NULL otherwise. The cursor stays at the same logical position, but the physical position may change if it is pointing to a compressed page that was reorganized.

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

Parameters

[in,out]	cursor	A page cursor
[in]	rec	record To insert
[in]	index	Record descriptor
[in,out]	offsets	rec_get_offsets(rec, index)
[in]	mtr	Mini-transaction handle, or NULL

Returns: pointer to record if succeed, NULL otherwise

◆ page_cur_search() [1/2]

static ulint page_cur_search	(	const buf_block_t *	block,
		const dict_index_t *	index,
		const dtuple_t *	tuple,
		page_cur_mode_t	mode,
		page_cur_t *	cursor
	)

inlinestatic

Search the right position for a page cursor.

Parameters

[in]	block	buffer block
[in]	index	index tree
[in]	tuple	data tuple
[in]	mode	PAGE_CUR_L, PAGE_CUR_LE, PAGE_CUR_G, or PAGE_CUR_GE
[out]	cursor	page cursor

Returns: number of matched fields on the left

◆ page_cur_search() [2/2]

static ulint page_cur_search	(	const buf_block_t *	block,
		const dict_index_t *	index,
		const dtuple_t *	tuple,
		page_cur_t *	cursor
	)

inlinestatic

Search the right position for a page cursor.

Parameters

[in]	block	buffer block
[in]	index	index tree
[in]	tuple	data tuple
[out]	cursor	page cursor

Returns: number of matched fields on the left

◆ page_cur_search_with_match()

void page_cur_search_with_match	(	const buf_block_t *	block,
		const dict_index_t *	index,
		const dtuple_t *	tuple,
		page_cur_mode_t	mode,
		ulint *	iup_matched_fields,
		ulint *	ilow_matched_fields,
		page_cur_t *	cursor,
		rtr_info_t *	rtr_info
	)

Searches the right position for a page cursor.

Parameters

[in]	block	Buffer block
[in]	index	Record descriptor
[in]	tuple	Data tuple
[in]	mode	PAGE_CUR_L, PAGE_CUR_LE, PAGE_CUR_G, or PAGE_CUR_GE
[in,out]	iup_matched_fields	Already matched fields in upper limit record
[in,out]	ilow_matched_fields	Already matched fields in lower limit record
[out]	cursor	Page cursor
[in,out]	rtr_info	Rtree search stack

◆ page_cur_search_with_match_bytes()

void page_cur_search_with_match_bytes	(	const buf_block_t *	block,
		const dict_index_t *	index,
		const dtuple_t *	tuple,
		page_cur_mode_t	mode,
		ulint *	iup_matched_fields,
		ulint *	iup_matched_bytes,
		ulint *	ilow_matched_fields,
		ulint *	ilow_matched_bytes,
		page_cur_t *	cursor
	)

Search the right position for a page cursor.

Parameters

[in]	block	buffer block
[in]	index	index tree
[in]	tuple	key to be searched for
[in]	mode	search mode
[in,out]	iup_matched_fields	already matched fields in the upper limit record
[in,out]	iup_matched_bytes	already matched bytes in the first partially matched field in the upper limit record
[in,out]	ilow_matched_fields	already matched fields in the lower limit record
[in,out]	ilow_matched_bytes	already matched bytes in the first partially matched field in the lower limit record
[out]	cursor	page cursor

◆ page_cur_set_after_last()

static void page_cur_set_after_last	(	const buf_block_t *	block,
		page_cur_t *	cur
	)

inlinestatic

Sets the cursor object to point after the last user record on the page.

Parameters

[in]	block	index page
[in]	cur	cursor

◆ page_cur_set_before_first()

static void page_cur_set_before_first	(	const buf_block_t *	block,
		page_cur_t *	cur
	)

inlinestatic

Sets the cursor object to point before the first user record on the page.

Parameters

[in]	block	index page
[in]	cur	cursor

◆ page_cur_tuple_insert()

static rec_t * page_cur_tuple_insert	(	page_cur_t *	cursor,
		const dtuple_t *	tuple,
		dict_index_t *	index,
		ulint **	offsets,
		mem_heap_t **	heap,
		mtr_t *	mtr
	)

inlinestatic

Inserts a record next to page cursor.

Returns pointer to inserted record if succeed, i.e., enough space available, NULL otherwise. The cursor stays at the same logical position, but the physical position may change if it is pointing to a compressed page that was reorganized.

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

Parameters

[in,out]	cursor	Page cursor.
[in]	tuple	Pointer to a data tuple
[in]	index	Index descriptor.
[in]	offsets	Offsets on *rec.
[in,out]	heap	Pointer to memory heap, or to nullptr.
[in]	mtr	Mini-transaction handle, or nullptr.

Returns: pointer to record if succeed, NULL otherwise

◆ page_delete_rec()

bool page_delete_rec	(	const dict_index_t *	index,
		page_cur_t *	pcur,
		const ulint *	offsets
	)

Removes the record from a leaf page.

This function does not log any changes. It is used by the IMPORT tablespace functions.

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

Parameters

[in]	index	The index that the record belongs to.
[in,out]	pcur	Page cursor on record to delete.
[in]	offsets	Offsets for record.

◆ page_parse_copy_rec_list_to_created_page()

const byte * page_parse_copy_rec_list_to_created_page	(	const byte *	ptr,
		const byte *	end_ptr,
		buf_block_t *	block,
		dict_index_t *	index,
		mtr_t *	mtr
	)

Parses a log record of copying a record list end to a new created page.

Returns: end of log record or NULL in: mtr or NULL; end of log record or NULL

Parameters

ptr	in: buffer
end_ptr	in: buffer end
block	in: page or NULL
index	in: record descriptor
mtr	in: mtr or NULL

Classes

Macros

Functions

Detailed Description

Macro Definition Documentation

◆ PAGE_CUR_ADAPT

Function Documentation

◆ page_copy_rec_list_end_to_created_page()

◆ page_cur_delete_rec()

◆ page_cur_direct_insert_rec_low()

◆ page_cur_get_block()

◆ page_cur_get_page()

◆ page_cur_get_page_zip()

◆ page_cur_get_rec()

◆ page_cur_insert_rec_low()

◆ page_cur_insert_rec_zip()

◆ page_cur_is_after_last()

◆ page_cur_is_before_first()

◆ page_cur_move_to_next()

◆ page_cur_move_to_prev()

◆ page_cur_open_on_rnd_user_rec()

◆ page_cur_parse_delete_rec()

◆ page_cur_parse_insert_rec()

◆ page_cur_position()

◆ page_cur_rec_insert()

◆ page_cur_search() [1/2]

◆ page_cur_search() [2/2]

◆ page_cur_search_with_match()

◆ page_cur_search_with_match_bytes()

◆ page_cur_set_after_last()

◆ page_cur_set_before_first()

◆ page_cur_tuple_insert()

◆ page_delete_rec()

◆ page_parse_copy_rec_list_to_created_page()