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/******************************************************
4
(c) 1994-1996 Innobase Oy
6
Created 2/2/1994 Heikki Tuuri
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*******************************************************/
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#include "page0types.h"
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#include "data0data.h"
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#include "dict0dict.h"
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#ifdef UNIV_MATERIALIZE
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Index page header starts at the first offset left free by the FIL-module */
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typedef byte page_header_t;
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#define PAGE_HEADER FSEG_PAGE_DATA /* index page header starts at this
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/*-----------------------------*/
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#define PAGE_N_DIR_SLOTS 0 /* number of slots in page directory */
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#define PAGE_HEAP_TOP 2 /* pointer to record heap top */
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#define PAGE_N_HEAP 4 /* number of records in the heap */
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#define PAGE_FREE 6 /* pointer to start of page free record list */
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#define PAGE_GARBAGE 8 /* number of bytes in deleted records */
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#define PAGE_LAST_INSERT 10 /* pointer to the last inserted record, or
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NULL if this info has been reset by a delete,
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#define PAGE_DIRECTION 12 /* last insert direction: PAGE_LEFT, ... */
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#define PAGE_N_DIRECTION 14 /* number of consecutive inserts to the same
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#define PAGE_N_RECS 16 /* number of user records on the page */
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#define PAGE_MAX_TRX_ID 18 /* highest id of a trx which may have modified
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a record on the page; a dulint; defined only
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in secondary indexes; specifically, not in an
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ibuf tree; NOTE: this may be modified only
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when the thread has an x-latch to the page,
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and ALSO an x-latch to btr_search_latch
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if there is a hash index to the page! */
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#define PAGE_HEADER_PRIV_END 26 /* end of private data structure of the page
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header which are set in a page create */
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#define PAGE_LEVEL 26 /* level of the node in an index tree; the
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leaf level is the level 0 */
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#define PAGE_INDEX_ID 28 /* index id where the page belongs */
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#define PAGE_BTR_SEG_LEAF 36 /* file segment header for the leaf pages in
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a B-tree: defined only on the root page of a
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B-tree, but not in the root of an ibuf tree */
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#define PAGE_BTR_IBUF_FREE_LIST PAGE_BTR_SEG_LEAF
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#define PAGE_BTR_IBUF_FREE_LIST_NODE PAGE_BTR_SEG_LEAF
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/* in the place of PAGE_BTR_SEG_LEAF and _TOP
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there is a free list base node if the page is
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the root page of an ibuf tree, and at the same
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place is the free list node if the page is in
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#define PAGE_BTR_SEG_TOP (36 + FSEG_HEADER_SIZE)
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/* file segment header for the non-leaf pages
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in a B-tree: defined only on the root page of
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a B-tree, but not in the root of an ibuf
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#define PAGE_DATA (PAGE_HEADER + 36 + 2 * FSEG_HEADER_SIZE)
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/* start of data on the page */
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#define PAGE_INFIMUM (PAGE_DATA + 1 + REC_N_EXTRA_BYTES)
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/* offset of the page infimum record on the
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#define PAGE_SUPREMUM (PAGE_DATA + 2 + 2 * REC_N_EXTRA_BYTES + 8)
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/* offset of the page supremum record on the
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#define PAGE_SUPREMUM_END (PAGE_SUPREMUM + 9)
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/* offset of the page supremum record end on
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/*-----------------------------*/
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/* Directions of cursor movement */
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#define PAGE_SAME_REC 3
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#define PAGE_SAME_PAGE 4
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#define PAGE_NO_DIRECTION 5
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typedef byte page_dir_slot_t;
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typedef page_dir_slot_t page_dir_t;
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/* Offset of the directory start down from the page end. We call the
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slot with the highest file address directory start, as it points to
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the first record in the list of records. */
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#define PAGE_DIR FIL_PAGE_DATA_END
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/* We define a slot in the page directory as two bytes */
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#define PAGE_DIR_SLOT_SIZE 2
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/* The offset of the physically lower end of the directory, counted from
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page end, when the page is empty */
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#define PAGE_EMPTY_DIR_START (PAGE_DIR + 2 * PAGE_DIR_SLOT_SIZE)
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/* The maximum and minimum number of records owned by a directory slot. The
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number may drop below the minimum in the first and the last slot in the
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#define PAGE_DIR_SLOT_MAX_N_OWNED 8
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#define PAGE_DIR_SLOT_MIN_N_OWNED 4
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/*****************************************************************
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Returns the max trx id field value. */
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page_t* page); /* in: page */
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/*****************************************************************
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Sets the max trx id field value. */
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page_t* page, /* in: page */
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dulint trx_id);/* in: transaction id */
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/*****************************************************************
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Sets the max trx id field value if trx_id is bigger than the previous
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page_update_max_trx_id(
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/*===================*/
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page_t* page, /* in: page */
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dulint trx_id); /* in: transaction id */
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/*****************************************************************
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Reads the given header field. */
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page_header_get_field(
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/*==================*/
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page_t* page, /* in: page */
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ulint field); /* in: PAGE_N_DIR_SLOTS, ... */
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/*****************************************************************
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Sets the given header field. */
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page_header_set_field(
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/*==================*/
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page_t* page, /* in: page */
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ulint field, /* in: PAGE_N_DIR_SLOTS, ... */
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ulint val); /* in: value */
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/*****************************************************************
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Returns the pointer stored in the given header field. */
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/* out: pointer or NULL */
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page_t* page, /* in: page */
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ulint field); /* in: PAGE_FREE, ... */
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/*****************************************************************
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Sets the pointer stored in the given header field. */
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page_t* page, /* in: page */
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ulint field, /* in: PAGE_FREE, ... */
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byte* ptr); /* in: pointer or NULL*/
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/*****************************************************************
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Resets the last insert info field in the page header. Writes to mlog
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about this operation. */
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page_header_reset_last_insert(
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/*==========================*/
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page_t* page, /* in: page */
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mtr_t* mtr); /* in: mtr */
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/****************************************************************
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Gets the first record on the page. */
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page_get_infimum_rec(
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/*=================*/
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/* out: the first record in record list */
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page_t* page); /* in: page which must have record(s) */
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/****************************************************************
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Gets the last record on the page. */
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page_get_supremum_rec(
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/*==================*/
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/* out: the last record in record list */
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page_t* page); /* in: page which must have record(s) */
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/****************************************************************
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Returns the middle record of record list. If there are an even number
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of records in the list, returns the first record of upper half-list. */
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/* out: middle record */
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page_t* page); /* in: page */
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/*****************************************************************
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Compares a data tuple to a physical record. Differs from the function
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cmp_dtuple_rec_with_match in the way that the record must reside on an
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index page, and also page infimum and supremum records can be given in
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the parameter rec. These are considered as the negative infinity and
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the positive infinity in the alphabetical order. */
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page_cmp_dtuple_rec_with_match(
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/*===========================*/
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/* out: 1, 0, -1, if dtuple is greater, equal,
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less than rec, respectively, when only the
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common first fields are compared */
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dtuple_t* dtuple, /* in: data tuple */
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rec_t* rec, /* in: physical record on a page; may also
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be page infimum or supremum, in which case
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matched-parameter values below are not
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ulint* matched_fields, /* in/out: number of already completely
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matched fields; when function returns
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contains the value for current comparison */
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ulint* matched_bytes); /* in/out: number of already matched
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bytes within the first field not completely
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matched; when function returns contains the
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value for current comparison */
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/*****************************************************************
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Gets the number of user records on page (the infimum and supremum records
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are not user records). */
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/* out: number of user records */
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page_t* page); /* in: index page */
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/*******************************************************************
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Returns the number of records before the given record in chain.
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The number includes infimum and supremum records. */
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page_rec_get_n_recs_before(
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/*=======================*/
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/* out: number of records */
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rec_t* rec); /* in: the physical record */
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/*****************************************************************
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Gets the number of dir slots in directory. */
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page_dir_get_n_slots(
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/*=================*/
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/* out: number of slots */
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page_t* page); /* in: index page */
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/*****************************************************************
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Gets pointer to nth directory slot. */
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page_dir_get_nth_slot(
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/*==================*/
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/* out: pointer to dir slot */
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page_t* page, /* in: index page */
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ulint n); /* in: position */
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/******************************************************************
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Used to check the consistency of a record on a page. */
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/* out: TRUE if succeed */
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rec_t* rec); /* in: record */
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/*******************************************************************
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Gets the record pointed to by a directory slot. */
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page_dir_slot_get_rec(
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/*==================*/
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/* out: pointer to record */
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page_dir_slot_t* slot); /* in: directory slot */
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/*******************************************************************
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This is used to set the record offset in a directory slot. */
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page_dir_slot_set_rec(
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/*==================*/
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page_dir_slot_t* slot, /* in: directory slot */
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rec_t* rec); /* in: record on the page */
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/*******************************************************************
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Gets the number of records owned by a directory slot. */
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page_dir_slot_get_n_owned(
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/*======================*/
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/* out: number of records */
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page_dir_slot_t* slot); /* in: page directory slot */
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/*******************************************************************
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This is used to set the owned records field of a directory slot. */
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page_dir_slot_set_n_owned(
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/*======================*/
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page_dir_slot_t* slot, /* in: directory slot */
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ulint n); /* in: number of records owned
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/****************************************************************
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Calculates the space reserved for directory slots of a given
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number of records. The exact value is a fraction number
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n * PAGE_DIR_SLOT_SIZE / PAGE_DIR_SLOT_MIN_N_OWNED, and it is
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rounded upwards to an integer. */
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page_dir_calc_reserved_space(
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/*=========================*/
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ulint n_recs); /* in: number of records */
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/*******************************************************************
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Looks for the directory slot which owns the given record. */
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page_dir_find_owner_slot(
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/*=====================*/
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/* out: the directory slot number */
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rec_t* rec); /* in: the physical record */
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/****************************************************************
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Gets the pointer to the next record on the page. */
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/* out: pointer to next record */
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rec_t* rec); /* in: pointer to record, must not be page
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/****************************************************************
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Sets the pointer to the next record on the page. */
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rec_t* rec, /* in: pointer to record, must not be
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rec_t* next); /* in: pointer to next record, must not
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/****************************************************************
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Gets the pointer to the previous record. */
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/* out: pointer to previous record */
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rec_t* rec); /* in: pointer to record, must not be page
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/****************************************************************
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TRUE if the record is a user record on the page. */
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page_rec_is_user_rec(
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/*=================*/
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/* out: TRUE if a user record */
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rec_t* rec); /* in: record */
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/****************************************************************
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TRUE if the record is the supremum record on a page. */
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page_rec_is_supremum(
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/*=================*/
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/* out: TRUE if the supremum record */
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rec_t* rec); /* in: record */
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/****************************************************************
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TRUE if the record is the infimum record on a page. */
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/* out: TRUE if the infimum record */
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rec_t* rec); /* in: record */
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/****************************************************************
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TRUE if the record is the first user record on the page. */
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page_rec_is_first_user_rec(
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/*=======================*/
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/* out: TRUE if first user record */
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rec_t* rec); /* in: record */
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/****************************************************************
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TRUE if the record is the last user record on the page. */
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page_rec_is_last_user_rec(
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/*======================*/
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/* out: TRUE if last user record */
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rec_t* rec); /* in: record */
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/*******************************************************************
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Looks for the record which owns the given record. */
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page_rec_find_owner_rec(
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/*====================*/
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/* out: the owner record */
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rec_t* rec); /* in: the physical record */
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/***************************************************************************
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This is a low-level operation which is used in a database index creation
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to update the page number of a created B-tree to a data dictionary
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page_rec_write_index_page_no(
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/*=========================*/
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rec_t* rec, /* in: record to update */
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ulint i, /* in: index of the field to update */
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ulint page_no,/* in: value to write */
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mtr_t* mtr); /* in: mtr */
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/****************************************************************
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Returns the maximum combined size of records which can be inserted on top
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page_get_max_insert_size(
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/*=====================*/
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/* out: maximum combined size for inserted records */
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page_t* page, /* in: index page */
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ulint n_recs); /* in: number of records */
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/****************************************************************
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Returns the maximum combined size of records which can be inserted on top
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of record heap if page is first reorganized. */
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page_get_max_insert_size_after_reorganize(
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/*======================================*/
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/* out: maximum combined size for inserted records */
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page_t* page, /* in: index page */
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ulint n_recs);/* in: number of records */
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/*****************************************************************
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Calculates free space if a page is emptied. */
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page_get_free_space_of_empty(void);
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/*==============================*/
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/* out: free space */
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/****************************************************************
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Returns the sum of the sizes of the records in the record list
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excluding the infimum and supremum records. */
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/* out: data in bytes */
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page_t* page); /* in: index page */
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/****************************************************************
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Allocates a block of memory from an index page. */
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/* out: pointer to start of allocated
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buffer, or NULL if allocation fails */
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page_t* page, /* in: index page */
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ulint need, /* in: number of bytes needed */
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ulint* heap_no);/* out: this contains the heap number
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of the allocated record if allocation succeeds */
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/****************************************************************
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Puts a record to free list. */
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page_t* page, /* in: index page */
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rec_t* rec); /* in: pointer to the (origin of) record */
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/**************************************************************
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The index page creation function. */
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/* out: pointer to the page */
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buf_frame_t* frame, /* in: a buffer frame where the page is
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mtr_t* mtr); /* in: mini-transaction handle */
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/*****************************************************************
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Differs from page_copy_rec_list_end, because this function does not
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touch the lock table and max trx id on page. */
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page_copy_rec_list_end_no_locks(
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/*============================*/
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page_t* new_page, /* in: index page to copy to */
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page_t* page, /* in: index page */
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rec_t* rec, /* in: record on page */
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mtr_t* mtr); /* in: mtr */
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/*****************************************************************
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Copies records from page to new_page, from the given record onward,
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including that record. Infimum and supremum records are not copied.
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The records are copied to the start of the record list on new_page. */
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page_copy_rec_list_end(
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/*===================*/
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page_t* new_page, /* in: index page to copy to */
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page_t* page, /* in: index page */
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rec_t* rec, /* in: record on page */
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mtr_t* mtr); /* in: mtr */
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/*****************************************************************
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Copies records from page to new_page, up to the given record, NOT
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including that record. Infimum and supremum records are not copied.
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The records are copied to the end of the record list on new_page. */
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page_copy_rec_list_start(
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/*=====================*/
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page_t* new_page, /* in: index page to copy to */
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page_t* page, /* in: index page */
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rec_t* rec, /* in: record on page */
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mtr_t* mtr); /* in: mtr */
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/*****************************************************************
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Deletes records from a page from a given record onward, including that record.
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The infimum and supremum records are not deleted. */
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page_delete_rec_list_end(
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/*=====================*/
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page_t* page, /* in: index page */
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rec_t* rec, /* in: record on page */
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ulint n_recs, /* in: number of records to delete, or ULINT_UNDEFINED
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ulint size, /* in: the sum of the sizes of the records in the end
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of the chain to delete, or ULINT_UNDEFINED if not
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mtr_t* mtr); /* in: mtr */
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/*****************************************************************
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Deletes records from page, up to the given record, NOT including
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that record. Infimum and supremum records are not deleted. */
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page_delete_rec_list_start(
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/*=======================*/
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page_t* page, /* in: index page */
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rec_t* rec, /* in: record on page */
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mtr_t* mtr); /* in: mtr */
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/*****************************************************************
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Moves record list end to another page. Moved records include
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page_move_rec_list_end(
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/*===================*/
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page_t* new_page, /* in: index page where to move */
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page_t* page, /* in: index page */
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rec_t* split_rec, /* in: first record to move */
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mtr_t* mtr); /* in: mtr */
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/*****************************************************************
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Moves record list start to another page. Moved records do not include
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page_move_rec_list_start(
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/*=====================*/
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page_t* new_page, /* in: index page where to move */
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page_t* page, /* in: index page */
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rec_t* split_rec, /* in: first record not to move */
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mtr_t* mtr); /* in: mtr */
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/********************************************************************
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Splits a directory slot which owns too many records. */
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page_t* page, /* in: the index page in question */
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ulint slot_no); /* in: the directory slot */
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/*****************************************************************
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Tries to balance the given directory slot with too few records
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with the upper neighbor, so that there are at least the minimum number
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of records owned by the slot; this may result in the merging of
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page_dir_balance_slot(
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/*==================*/
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page_t* page, /* in: index page */
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ulint slot_no); /* in: the directory slot */
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/**************************************************************
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Parses a log record of a record list end or start deletion. */
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page_parse_delete_rec_list(
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/*=======================*/
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/* out: end of log record or NULL */
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byte type, /* in: MLOG_LIST_END_DELETE or MLOG_LIST_START_DELETE */
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byte* ptr, /* in: buffer */
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byte* end_ptr,/* in: buffer end */
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page_t* page, /* in: page or NULL */
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mtr_t* mtr); /* in: mtr or NULL */
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/***************************************************************
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Parses a redo log record of creating a page. */
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/* out: end of log record or NULL */
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byte* ptr, /* in: buffer */
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byte* end_ptr,/* in: buffer end */
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page_t* page, /* in: page or NULL */
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mtr_t* mtr); /* in: mtr or NULL */
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/****************************************************************
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Prints record contents including the data relevant only in
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the index page context. */
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/*******************************************************************
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This is used to print the contents of the directory for
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debugging purposes. */
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page_t* page, /* in: index page */
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ulint pr_n); /* in: print n first and n last entries */
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/*******************************************************************
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This is used to print the contents of the page record list for
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debugging purposes. */
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page_t* page, /* in: index page */
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ulint pr_n); /* in: print n first and n last entries */
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/*******************************************************************
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Prints the info in a page header. */
648
/*******************************************************************
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This is used to print the contents of the page for
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debugging purposes. */
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page_t* page, /* in: index page */
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ulint dn, /* in: print dn first and last entries in directory */
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ulint rn); /* in: print rn first and last records on page */
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/*******************************************************************
659
The following is used to validate a record on a page. This function
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differs from rec_validate as it can also check the n_owned field and
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the heap_no field. */
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/* out: TRUE if ok */
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rec_t* rec); /* in: record on the page */
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/*******************************************************************
669
This function checks the consistency of an index page. */
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/* out: TRUE if ok */
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page_t* page, /* in: index page */
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dict_index_t* index); /* in: data dictionary index containing
677
the page record type definition */
678
/*******************************************************************
679
Looks in the page record list for a record with the given heap number. */
682
page_find_rec_with_heap_no(
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/*=======================*/
684
/* out: record, NULL if not found */
685
page_t* page, /* in: index page */
686
ulint heap_no);/* in: heap number */
688
#ifdef UNIV_MATERIALIZE
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#define UNIV_INLINE UNIV_INLINE_ORIGINAL
694
#include "page0page.ic"
added
removed
innobase/include/page0page.h
