WL#2535 - smarter "index merge" in fulltext

This commit is contained in:
svoj@mysql.com 2005-05-27 00:43:40 +05:00
parent 30def9f3f8
commit 5193b4ec70

View file

@ -18,6 +18,27 @@
/* TODO: add caching - pre-read several index entries at once */
/*
Added optimization for full-text queries with plus-words. It was
implemented by sharing maximal document id (max_docid) variable
inside plus subtree. max_docid could be used by any word in plus
subtree, but it could be updated by plus-word only.
The idea is: there is no need to search for docid smaller than
biggest docid inside current plus subtree.
Examples:
+word1 word2
share same max_docid
max_docid updated by word1
+word1 +(word2 word3)
share same max_docid
max_docid updated by word1
+(word1 -word2) +(+word3 word4)
share same max_docid
max_docid updated by word3
*/
#define FT_CORE
#include "ftdefs.h"
@ -66,6 +87,7 @@ struct st_ftb_expr
uint flags;
/* ^^^^^^^^^^^^^^^^^^ FTB_{EXPR,WORD} common section */
my_off_t docid[2];
my_off_t max_docid;
float weight;
float cur_weight;
LIST *phrase; /* phrase words */
@ -82,6 +104,7 @@ typedef struct st_ftb_word
/* ^^^^^^^^^^^^^^^^^^ FTB_{EXPR,WORD} common section */
my_off_t docid[2]; /* for index search and for scan */
my_off_t key_root;
my_off_t *max_docid;
MI_KEYDEF *keyinfo;
float weight;
uint ndepth;
@ -139,6 +162,7 @@ static void _ftb_parse_query(FTB *ftb, byte **start, byte *end,
FT_WORD w;
FTB_WORD *ftbw;
FTB_EXPR *ftbe;
FTB_EXPR *tmp_expr;
FT_WORD *phrase_word;
LIST *phrase_list;
uint extra=HA_FT_WLEN+ftb->info->s->rec_reflength; /* just a shortcut */
@ -174,6 +198,10 @@ static void _ftb_parse_query(FTB *ftb, byte **start, byte *end,
if (param.yesno > 0) up->ythresh++;
queue_insert(& ftb->queue, (byte *)ftbw);
ftb->with_scan|=(param.trunc & FTB_FLAG_TRUNC);
for (tmp_expr= up; tmp_expr->up; tmp_expr= tmp_expr->up)
if (! (tmp_expr->flags & FTB_FLAG_YES))
break;
ftbw->max_docid= &tmp_expr->max_docid;
case 4: /* not indexed word (stopword or too short/long) */
if (! up_quot) break;
phrase_word= (FT_WORD *)alloc_root(&ftb->mem_root, sizeof(FT_WORD));
@ -190,7 +218,7 @@ static void _ftb_parse_query(FTB *ftb, byte **start, byte *end,
if (param.yesno<0) ftbe->flags|=FTB_FLAG_NO;
ftbe->weight=weight;
ftbe->up=up;
ftbe->ythresh=ftbe->yweaks=0;
ftbe->max_docid= ftbe->ythresh= ftbe->yweaks= 0;
ftbe->docid[0]=ftbe->docid[1]=HA_OFFSET_ERROR;
ftbe->phrase= NULL;
if (param.quot) ftb->with_scan|=2;
@ -236,8 +264,15 @@ static int _ft2_search(FTB *ftb, FTB_WORD *ftbw, my_bool init_search)
}
else
{
uint sflag= SEARCH_BIGGER;
if (ftbw->docid[0] < *ftbw->max_docid)
{
sflag|= SEARCH_SAME;
_mi_dpointer(info, (uchar *)(ftbw->word + ftbw->len + HA_FT_WLEN),
*ftbw->max_docid);
}
r=_mi_search(info, ftbw->keyinfo, (uchar*) lastkey_buf,
USE_WHOLE_KEY, SEARCH_BIGGER, ftbw->key_root);
USE_WHOLE_KEY, sflag, ftbw->key_root);
}
can_go_down=(!ftbw->off && (init_search || (ftbw->flags & FTB_FLAG_TRUNC)));
@ -313,6 +348,8 @@ static int _ft2_search(FTB *ftb, FTB_WORD *ftbw, my_bool init_search)
memcpy(lastkey_buf+off, info->lastkey, info->lastkey_length);
}
ftbw->docid[0]=info->lastpos;
if (ftbw->flags & FTB_FLAG_YES)
*ftbw->max_docid= info->lastpos;
return 0;
}
@ -422,7 +459,7 @@ FT_INFO * ft_init_boolean_search(MI_INFO *info, uint keynr, byte *query,
ftbe->flags=FTB_FLAG_YES;
ftbe->nos=1;
ftbe->up=0;
ftbe->ythresh=ftbe->yweaks=0;
ftbe->max_docid= ftbe->ythresh= ftbe->yweaks= 0;
ftbe->docid[0]=ftbe->docid[1]=HA_OFFSET_ERROR;
ftbe->phrase= NULL;
ftb->root=ftbe;