mirror of
https://github.com/MariaDB/server.git
synced 2025-01-31 19:11:46 +01:00
67456bb970
Link adaptive hash index entries to the buffer page, so that we can remove them quickly without knowing the record structure on that page; this was requested by Marko for the compact InnoDB table format; note that the adaptive hash index memory overhead grows by 67 %, maybe we have to tune this later somehow
154 lines
5.1 KiB
C
154 lines
5.1 KiB
C
/******************************************************
|
|
The hash table with external chains
|
|
|
|
(c) 1994-1997 Innobase Oy
|
|
|
|
Created 8/18/1994 Heikki Tuuri
|
|
*******************************************************/
|
|
|
|
#ifndef ha0ha_h
|
|
#define ha0ha_h
|
|
|
|
#include "univ.i"
|
|
|
|
#include "hash0hash.h"
|
|
#include "page0types.h"
|
|
|
|
/*****************************************************************
|
|
Looks for an element in a hash table. */
|
|
UNIV_INLINE
|
|
void*
|
|
ha_search_and_get_data(
|
|
/*===================*/
|
|
/* out: pointer to the data of the first hash
|
|
table node in chain having the fold number,
|
|
NULL if not found */
|
|
hash_table_t* table, /* in: hash table */
|
|
ulint fold); /* in: folded value of the searched data */
|
|
/*************************************************************
|
|
Looks for an element when we know the pointer to the data and updates
|
|
the pointer to data if found. */
|
|
|
|
void
|
|
ha_search_and_update_if_found(
|
|
/*==========================*/
|
|
hash_table_t* table, /* in: hash table */
|
|
ulint fold, /* in: folded value of the searched data */
|
|
void* data, /* in: pointer to the data */
|
|
void* new_data);/* in: new pointer to the data */
|
|
/*****************************************************************
|
|
Creates a hash table with >= n array cells. The actual number of cells is
|
|
chosen to be a prime number slightly bigger than n. */
|
|
|
|
hash_table_t*
|
|
ha_create(
|
|
/*======*/
|
|
/* out, own: created table */
|
|
ibool in_btr_search, /* in: TRUE if the hash table is used in
|
|
the btr_search module */
|
|
ulint n, /* in: number of array cells */
|
|
ulint n_mutexes, /* in: number of mutexes to protect the
|
|
hash table: must be a power of 2 */
|
|
ulint mutex_level); /* in: level of the mutexes in the latching
|
|
order: this is used in the debug version */
|
|
/*****************************************************************
|
|
Inserts an entry into a hash table. If an entry with the same fold number
|
|
is found, its node is updated to point to the new data, and no new node
|
|
is inserted. This function is only used in the adaptive hash index. */
|
|
|
|
ibool
|
|
ha_insert_for_fold(
|
|
/*===============*/
|
|
/* out: TRUE if succeed, FALSE if no more
|
|
memory could be allocated */
|
|
hash_table_t* table, /* in: hash table */
|
|
ulint fold, /* in: folded value of data; if a node with
|
|
the same fold value already exists, it is
|
|
updated to point to the same data, and no new
|
|
node is created! */
|
|
void* data); /* in: data, must not be NULL */
|
|
/*****************************************************************
|
|
Reserves the necessary hash table mutex and inserts an entry into the hash
|
|
table. */
|
|
UNIV_INLINE
|
|
ibool
|
|
ha_insert_for_fold_mutex(
|
|
/*=====================*/
|
|
/* out: TRUE if succeed, FALSE if no more
|
|
memory could be allocated */
|
|
hash_table_t* table, /* in: hash table */
|
|
ulint fold, /* in: folded value of data; if a node with
|
|
the same fold value already exists, it is
|
|
updated to point to the same data, and no new
|
|
node is created! */
|
|
void* data); /* in: data, must not be NULL */
|
|
/*****************************************************************
|
|
Deletes an entry from a hash table. */
|
|
|
|
void
|
|
ha_delete(
|
|
/*======*/
|
|
hash_table_t* table, /* in: hash table */
|
|
ulint fold, /* in: folded value of data */
|
|
void* data); /* in: data, must not be NULL and must exist
|
|
in the hash table */
|
|
/*************************************************************
|
|
Looks for an element when we know the pointer to the data and deletes
|
|
it from the hash table if found. */
|
|
UNIV_INLINE
|
|
ibool
|
|
ha_search_and_delete_if_found(
|
|
/*==========================*/
|
|
/* out: TRUE if found */
|
|
hash_table_t* table, /* in: hash table */
|
|
ulint fold, /* in: folded value of the searched data */
|
|
void* data); /* in: pointer to the data */
|
|
/*********************************************************************
|
|
Removes from the chain determined by fold all nodes whose data pointer
|
|
points to the page given. */
|
|
|
|
void
|
|
ha_remove_all_nodes_to_page(
|
|
/*========================*/
|
|
hash_table_t* table, /* in: hash table */
|
|
page_t* page); /* in: buffer page */
|
|
/*****************************************************************
|
|
Validates a hash table. */
|
|
|
|
ibool
|
|
ha_validate(
|
|
/*========*/
|
|
/* out: TRUE if ok */
|
|
hash_table_t* table); /* in: hash table */
|
|
/*****************************************************************
|
|
Prints info of a hash table. */
|
|
|
|
void
|
|
ha_print_info(
|
|
/*==========*/
|
|
FILE* file, /* in: file where to print */
|
|
hash_table_t* table); /* in: hash table */
|
|
|
|
/* The hash table external chain node */
|
|
|
|
typedef struct ha_node_struct ha_node_t;
|
|
struct ha_node_struct {
|
|
ha_node_t* next; /* next chain node; NULL if none */
|
|
void* data; /* pointer to the data */
|
|
ulint fold; /* fold value for the data */
|
|
ha_node_t* next_for_block;/* in an adaptive hash index
|
|
(btr0sea.c), a doubly linked list of hash
|
|
nodes for the buffer block; these nodes
|
|
contain pointers to index records on the
|
|
page; in the last node this field is NULL;
|
|
note that we do not use UT_LST_ macros
|
|
to manipulate this list */
|
|
ha_node_t* prev_for_block;/* pointer to the previous node; in the
|
|
first node NULL */
|
|
};
|
|
|
|
#ifndef UNIV_NONINL
|
|
#include "ha0ha.ic"
|
|
#endif
|
|
|
|
#endif
|