Fix YA text phrase search bug.

checkcondition_str() failed to report multiple matches for a prefix
pattern correctly: it would dutifully merge the match positions, but
then after exiting that loop, if the last prefix-matching word had
had no suitable positions, it would report there were no matches.
The upshot would be failing to recognize a match that the query
should match.

It looks like you need all of these conditions to see the bug:
* a phrase search (else we don't ask for match position details)
* a prefix search item (else we don't get to this code)
* a weight restriction (else checkclass_str won't fail)

Noted while investigating a problem report from Pavel Borisov,
though this is distinct from the issue he was on about.

Back-patch to 9.6 where phrase search was added.
This commit is contained in:
Tom Lane 2020-05-07 15:59:51 -04:00
parent b2fd8ebe23
commit db89f0e3a4
3 changed files with 28 additions and 1 deletions

View File

@ -1276,12 +1276,13 @@ checkcondition_str(void *checkval, QueryOperand *val, ExecPhraseData *data)
WordEntry *StopLow = chkval->arrb;
WordEntry *StopHigh = chkval->arre;
WordEntry *StopMiddle = StopHigh;
int difference = -1;
bool res = false;
/* Loop invariant: StopLow <= val < StopHigh */
while (StopLow < StopHigh)
{
int difference;
StopMiddle = StopLow + (StopHigh - StopLow) / 2;
difference = tsCompareString(chkval->operand + val->distance,
val->length,
@ -1347,6 +1348,11 @@ checkcondition_str(void *checkval, QueryOperand *val, ExecPhraseData *data)
memcpy(allpos + npos, data->pos, sizeof(WordEntryPos) * data->npos);
npos += data->npos;
}
else
{
/* at loop exit, res must be true if we found matches */
res = (npos > 0);
}
}
else
{

View File

@ -533,6 +533,24 @@ SELECT 'a b:89 ca:23A,64c cb:80b d:34c'::tsvector @@ 'd:AC & c:*B' as "true";
t
(1 row)
SELECT 'wa:1D wb:2A'::tsvector @@ 'w:*D & w:*A'::tsquery as "true";
true
------
t
(1 row)
SELECT 'wa:1D wb:2A'::tsvector @@ 'w:*D <-> w:*A'::tsquery as "true";
true
------
t
(1 row)
SELECT 'wa:1A wb:2D'::tsvector @@ 'w:*D <-> w:*A'::tsquery as "false";
false
-------
f
(1 row)
SELECT 'supernova'::tsvector @@ 'super'::tsquery AS "false";
false
-------

View File

@ -101,6 +101,9 @@ SELECT 'a b:89 ca:23A,64b d:34c'::tsvector @@ 'd:AC & c:*CB' as "true";
SELECT 'a b:89 ca:23A,64b cb:80c d:34c'::tsvector @@ 'd:AC & c:*C' as "true";
SELECT 'a b:89 ca:23A,64c cb:80b d:34c'::tsvector @@ 'd:AC & c:*C' as "true";
SELECT 'a b:89 ca:23A,64c cb:80b d:34c'::tsvector @@ 'd:AC & c:*B' as "true";
SELECT 'wa:1D wb:2A'::tsvector @@ 'w:*D & w:*A'::tsquery as "true";
SELECT 'wa:1D wb:2A'::tsvector @@ 'w:*D <-> w:*A'::tsquery as "true";
SELECT 'wa:1A wb:2D'::tsvector @@ 'w:*D <-> w:*A'::tsquery as "false";
SELECT 'supernova'::tsvector @@ 'super'::tsquery AS "false";
SELECT 'supeanova supernova'::tsvector @@ 'super'::tsquery AS "false";