mariadb/heap/heapdef.h
unknown bfe2425aad WL#1687 - Optimize UNION DISTINCT ... UNION ALL (again).
HEAP: Copies the key count to a backup variable and sets the key count to zero.
That way, no HEAP function will ever try to touch any index.
Re-enabling is done by copying back the backup variable.
To avoid memory leak at table close, disable deletes all index trees.
Re-enabling must be done with empty indexes and data anyway. Otherwise,
the indexes would need to be repaired, wich HEAP is not capable of.
MyISAM: Only the key_map is cleared and set.
Re-enabling must be done with empty indexes and data. Otherwise, repair needs
to be done which will enable all keys persistently.
The former implementation disabled only non-unique keys and maked this persistent.
The new implementation additionally can disable all keys, but only without
making this persistent. Re-enabling all keys can be done without repair,
if data file and indexes are empty.


heap/heapdef.h:
  WL#1687 - Optimize UNION DISTINCT ... UNION ALL (again).
  Pulled hp_clear_keys() out of hp_clear().
heap/hp_clear.c:
  WL#1687 - Optimize UNION DISTINCT ... UNION ALL (again).
  Pulled hp_clear_keys() out of hp_clear().
  Added the new functions for disabling and enabling keys and to ask for the key state.
include/heap.h:
  WL#1687 - Optimize UNION DISTINCT ... UNION ALL (again).
  Added a new HP_SHARE element to save the key count while keys are disabled.
  Added declarations for the new functions.
myisam/mi_open.c:
  WL#1687 - Optimize UNION DISTINCT ... UNION ALL (again).
  Added the new functions for disabling and enabling keys and to ask for the key state.
myisam/myisamdef.h:
  WL#1687 - Optimize UNION DISTINCT ... UNION ALL (again).
  Added declarations for the new functions.
sql/ha_heap.cc:
  WL#1687 - Optimize UNION DISTINCT ... UNION ALL (again).
  Pulled set_keys_for_scanning() out of open().
  Added the new functions for disabling and enabling keys and to ask for the key state.
sql/ha_heap.h:
  WL#1687 - Optimize UNION DISTINCT ... UNION ALL (again).
  Added declarations for the new functions.
sql/ha_myisam.cc:
  WL#1687 - Optimize UNION DISTINCT ... UNION ALL (again).
  Extended disable_indexes() for all keys and no save.
  The argument is now 'mode' as it must handle different cases.
  Extended enable_indexes() for no save.
  The new feature needs the new argument 'mode' with the same semantics as in disable_indexes().
  Added indexes_are_disabled() to ask for the key state.
  Extended the existing call to enable_indexes() by the new argument.
sql/ha_myisam.h:
  WL#1687 - Optimize UNION DISTINCT ... UNION ALL (again).
  Modified the declarations of dis-/enable_indexes() for the new argument.
  Added the declaration of the new function to ask for the key state.
sql/handler.h:
  WL#1687 - Optimize UNION DISTINCT ... UNION ALL (again).
  Added declarations for the operation modes for the key switching functions.
  Modified the declarations of dis-/enable_indexes() for the new argument.
  Added the declaration of the new function to ask for the key state.
sql/sql_select.cc:
  WL#1687 - Optimize UNION DISTINCT ... UNION ALL (again).
  In create_myisam_from_heap() take notice of disabled keys
  and disable them in the new table before copying the data.
sql/sql_table.cc:
  WL#1687 - Optimize UNION DISTINCT ... UNION ALL (again).
  Modified the calls of dis-/enable_indexes() for the new argument.
2004-05-06 15:53:01 +02:00

108 lines
4.1 KiB
C

/* Copyright (C) 2000,2004 MySQL AB & MySQL Finland AB & TCX DataKonsult AB
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
/* This file is included in all heap-files */
#include <my_base.h> /* This includes global */
#ifdef THREAD
#include <my_pthread.h>
#endif
#include "heap.h" /* Structs & some defines */
#include "my_tree.h"
/*
When allocating keys /rows in the internal block structure, do it
within the following boundaries.
The challenge is to find the balance between allocate as few blocks
as possible and keep memory consumption down.
*/
#define HP_MIN_RECORDS_IN_BLOCK 16
#define HP_MAX_RECORDS_IN_BLOCK 8192
/* Some extern variables */
extern LIST *heap_open_list,*heap_share_list;
#define test_active(info) \
if (!(info->update & HA_STATE_AKTIV))\
{ my_errno=HA_ERR_NO_ACTIVE_RECORD; DBUG_RETURN(-1); }
#define hp_find_hash(A,B) ((HASH_INFO*) hp_find_block((A),(B)))
/* Find pos for record and update it in info->current_ptr */
#define hp_find_record(info,pos) (info)->current_ptr= hp_find_block(&(info)->s->block,pos)
typedef struct st_hp_hash_info
{
struct st_hp_hash_info *next_key;
byte *ptr_to_rec;
} HASH_INFO;
typedef struct {
HA_KEYSEG *keyseg;
uint key_length;
uint search_flag;
} heap_rb_param;
/* Prototypes for intern functions */
extern HP_SHARE *hp_find_named_heap(const char *name);
extern int hp_rectest(HP_INFO *info,const byte *old);
extern byte *hp_find_block(HP_BLOCK *info,ulong pos);
extern int hp_get_new_block(HP_BLOCK *info, ulong* alloc_length);
extern void hp_free(HP_SHARE *info);
extern byte *hp_free_level(HP_BLOCK *block,uint level,HP_PTRS *pos,
byte *last_pos);
extern int hp_write_key(HP_INFO *info, HP_KEYDEF *keyinfo,
const byte *record, byte *recpos);
extern int hp_rb_write_key(HP_INFO *info, HP_KEYDEF *keyinfo,
const byte *record, byte *recpos);
extern int hp_rb_delete_key(HP_INFO *info,HP_KEYDEF *keyinfo,
const byte *record,byte *recpos,int flag);
extern int hp_delete_key(HP_INFO *info,HP_KEYDEF *keyinfo,
const byte *record,byte *recpos,int flag);
extern HASH_INFO *_heap_find_hash(HP_BLOCK *block,ulong pos);
extern byte *hp_search(HP_INFO *info,HP_KEYDEF *keyinfo,const byte *key,
uint nextflag);
extern byte *hp_search_next(HP_INFO *info, HP_KEYDEF *keyinfo,
const byte *key, HASH_INFO *pos);
extern ulong hp_hashnr(HP_KEYDEF *keyinfo,const byte *key);
extern ulong hp_rec_hashnr(HP_KEYDEF *keyinfo,const byte *rec);
extern ulong hp_mask(ulong hashnr,ulong buffmax,ulong maxlength);
extern void hp_movelink(HASH_INFO *pos,HASH_INFO *next_link,
HASH_INFO *newlink);
extern int hp_rec_key_cmp(HP_KEYDEF *keydef,const byte *rec1,
const byte *rec2);
extern int hp_key_cmp(HP_KEYDEF *keydef,const byte *rec,
const byte *key);
extern void hp_make_key(HP_KEYDEF *keydef,byte *key,const byte *rec);
extern uint hp_rb_make_key(HP_KEYDEF *keydef, byte *key,
const byte *rec, byte *recpos);
extern uint hp_rb_key_length(HP_KEYDEF *keydef, const byte *key);
extern uint hp_rb_null_key_length(HP_KEYDEF *keydef, const byte *key);
extern my_bool hp_if_null_in_key(HP_KEYDEF *keyinfo, const byte *record);
extern int hp_close(register HP_INFO *info);
extern void hp_clear(HP_SHARE *info);
extern void hp_clear_keys(HP_SHARE *info);
extern uint hp_rb_pack_key(HP_KEYDEF *keydef, uchar *key, const uchar *old,
uint k_len);
#ifdef THREAD
extern pthread_mutex_t THR_LOCK_heap;
#else
#define pthread_mutex_lock(A)
#define pthread_mutex_unlock(A)
#endif