btr_cur_t Struct Reference

#include <btr0cur.h>

Collaboration diagram for btr_cur_t:

Public Attributes
dict_index_t *	index
page_cur_t	page_cur
purge_node_t *	purge_node
buf_block_t *	left_block
que_thr_t *	thr
btr_path_t *	path_arr
enum btr_cur_method	flag
ulint	tree_height
ulint	up_match
ulint	up_bytes
ulint	low_match
ulint	low_bytes
ulint	n_fields
ulint	n_bytes
ulint	fold

Detailed Description

The tree cursor: the definition appears here only for the compiler

to know struct size!

Definition at line 781 of file btr0cur.h.

Member Data Documentation

enum btr_cur_method btr_cur_t::flag

The following fields are used in

btr_cur_search_to_nth_level to pass information: Search method used

Definition at line 801 of file btr0cur.h.

ulint btr_cur_t::fold

fold value used in the search if flag is BTR_CUR_HASH

Definition at line 839 of file btr0cur.h.

dict_index_t* btr_cur_t::index

index where positioned

Definition at line 782 of file btr0cur.h.

buf_block_t* btr_cur_t::left_block

this field is used to store a pointer to the left neighbor page, in the cases BTR_SEARCH_PREV and BTR_MODIFY_PREV

Definition at line 785 of file btr0cur.h.

ulint btr_cur_t::low_bytes

number of matched bytes to the right at the time cursor positioned; only used internally in searches: not defined after the search

Definition at line 831 of file btr0cur.h.

ulint btr_cur_t::low_match

if search mode was PAGE_CUR_LE, the number of matched fields to the first user record AT THE CURSOR or to the left of it after btr_cur_search_to_nth_level; NOT defined for PAGE_CUR_GE or any other search modes; see also the NOTE in up_match!

Definition at line 823 of file btr0cur.h.

ulint btr_cur_t::n_bytes

hash prefix bytes if hash_node != NULL

Definition at line 837 of file btr0cur.h.

ulint btr_cur_t::n_fields

prefix length used in a hash search if hash_node != NULL

Definition at line 835 of file btr0cur.h.

page_cur_t btr_cur_t::page_cur

page cursor

Definition at line 783 of file btr0cur.h.

btr_path_t* btr_cur_t::path_arr

in estimating the number of rows in range, we store in this array information of the path through the tree

Definition at line 842 of file btr0cur.h.

purge_node_t* btr_cur_t::purge_node

purge node, for BTR_DELETE

Definition at line 784 of file btr0cur.h.

que_thr_t* btr_cur_t::thr

this field is only used when btr_cur_search_to_nth_level is called for an index entry insertion: the calling query thread is passed here to be used in the insert buffer

Definition at line 791 of file btr0cur.h.

ulint btr_cur_t::tree_height

Tree height if the search is done for a pessimistic insert or update operation

Definition at line 802 of file btr0cur.h.

ulint btr_cur_t::up_bytes

number of matched bytes to the right at the time cursor positioned; only used internally in searches: not defined after the search

Definition at line 819 of file btr0cur.h.

ulint btr_cur_t::up_match

If the search mode was PAGE_CUR_LE, the number of matched fields to the the first user record to the right of the cursor record after btr_cur_search_to_nth_level; for the mode PAGE_CUR_GE, the matched fields to the first user record AT THE CURSOR or to the right of it; NOTE that the up_match and low_match values may exceed the correct values for comparison to the adjacent user record if that record is on a different leaf page! (See the note in row_ins_duplicate_error_in_clust.)

Definition at line 805 of file btr0cur.h.

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The documentation for this struct was generated from the following file:

• storage/innobase/include/btr0cur.h