WL#2535 - smarter "index merge" in fulltext (289d3bc2) · Commits · Software / OSDI20 Artifacts / mariadb

storage/myisam/ft_boolean_search.c

+40 −3

Original line number	Diff line number	Diff line
		@@ -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;