mirror/postgresql
2
0
Fork 0
mirror of https://git.postgresql.org/git/postgresql.git synced 2025-01-12 18:34:36 +08:00
Code Issues Packages Projects Releases Wiki Activity

1 Fix problem with lost precision in rank with OR-ed lexemes

Browse Source 
2 Allow tsquery_in to input void tsquery: resolve dump/restore problem with tsquery
This commit is contained in:
Teodor Sigaev 2005-10-28 13:05:06 +00:00
parent fbff2e9607
commit 21b748e76a
3 changed files with 49 additions and 23 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

18
contrib/tsearch2/expected/tsearch2.out
View File

@ -746,21 +746,21 @@ select count(*) FROM test_tsvector WHERE a @@ to_tsquery('copyright');
(1 row)
select rank(' a:1 s:2C d g'::tsvector, 'a | s');
rank
------
0.28
rank
-----------
0.0911891
(1 row)
select rank(' a:1 s:2B d g'::tsvector, 'a | s');
rank
------
0.46
rank
----------
0.151982
(1 row)
select rank(' a:1 s:2 d g'::tsvector, 'a | s');
rank
------
0.19
rank
-----------
0.0607927
(1 row)
select rank(' a:1 s:2C d g'::tsvector, 'a & s');

23
contrib/tsearch2/query.c
View File

@ -55,6 +55,7 @@ Datum to_tsquery_current(PG_FUNCTION_ARGS);
/* parser's states */
#define WAITOPERAND 1
#define WAITOPERATOR 2
#define WAITFIRSTOPERAND 3
/*
* node of query tree, also used
@ -137,6 +138,7 @@ gettoken_query(QPRS_STATE * state, int4 *val, int4 *lenval, char **strval, int2
{
switch (state->state)
{
case WAITFIRSTOPERAND:
case WAITOPERAND:
if (*(state->buf) == '!')
{
@ -159,14 +161,16 @@ gettoken_query(QPRS_STATE * state, int4 *val, int4 *lenval, char **strval, int2
else if (*(state->buf) != ' ')
{
state->valstate.prsbuf = state->buf;
state->state = WAITOPERATOR;
if (gettoken_tsvector(&(state->valstate)))
{
*strval = state->valstate.word;
*lenval = state->valstate.curpos - state->valstate.word;
state->buf = get_weight(state->valstate.prsbuf, weight);
state->state = WAITOPERATOR;
return VAL;
}
else if ( state->state == WAITFIRSTOPERAND )
return END;
else
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
@ -596,7 +600,7 @@ static QUERYTYPE *
/* init state */
state.buf = buf;
state.state = WAITOPERAND;
state.state = WAITFIRSTOPERAND;
state.count = 0;
state.num = 0;
state.str = NULL;
@ -616,10 +620,13 @@ static QUERYTYPE *
/* parse query & make polish notation (postfix, but in reverse order) */
makepol(&state, pushval);
pfree(state.valstate.word);
if (!state.num)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("empty query")));
if (!state.num) {
elog(NOTICE, "Query doesn't contain lexem(s)");
query = (QUERYTYPE*)palloc( HDRSIZEQT );
query->len = HDRSIZEQT;
query->size = 0;
return query;
}
/* make finish struct */
commonlen = COMPUTESIZE(state.num, state.sumlen);
@ -905,6 +912,10 @@ to_tsquery(PG_FUNCTION_ARGS)
PG_FREE_IF_COPY(in, 1);
query = queryin(str, pushval_morph, PG_GETARG_INT32(0));
if ( query->size == 0 )
PG_RETURN_POINTER(query);
res = clean_fakeval_v2(GETQUERY(query), &len);
if (!res)
{

31
contrib/tsearch2/rank.c
View File

@ -257,7 +257,7 @@ calc_rank_or(float *w, tsvector * t, QUERYTYPE * q)
int4 dimt,
j,
i;
float res = -1.0;
float res = 0.0;
ITEM **item;
int size = q->size;
@ -266,6 +266,8 @@ calc_rank_or(float *w, tsvector * t, QUERYTYPE * q)
for (i = 0; i < size; i++)
{
float resj,wjm;
int4 jm;
entry = find_wordentry(t, q, item[i]);
if (!entry)
continue;
@ -281,14 +283,27 @@ calc_rank_or(float *w, tsvector * t, QUERYTYPE * q)
post = POSNULL + 1;
}
for (j = 0; j < dimt; j++)
{
if (res < 0)
res = wpos(post[j]);
else
res = 1.0 - (1.0 - res) * (1.0 - wpos(post[j]));
}
resj = 0.0;
wjm = -1.0;
jm = 0;
for (j = 0; j < dimt; j++)
{
resj = resj + wpos(post[j])/((j+1)*(j+1));
if ( wpos(post[j]) > wjm ) {
wjm = wpos(post[j]);
jm = j;
}
}
/*
limit (sum(i/i^2),i->inf) = pi^2/6
resj = sum(wi/i^2),i=1,noccurence,
wi - should be sorted desc,
don't sort for now, just choose maximum weight. This should be corrected
Oleg Bartunov
*/
res = res + ( wjm + resj - wjm/((jm+1)*(jm+1)))/1.64493406685;
}
res = res /size;
pfree(item);
return res;
}