diff options
Diffstat (limited to 'contrib/pg_trgm/trgm_gist.c')
| -rw-r--r-- | contrib/pg_trgm/trgm_gist.c | 33 |
1 files changed, 25 insertions, 8 deletions
diff --git a/contrib/pg_trgm/trgm_gist.c b/contrib/pg_trgm/trgm_gist.c index cbd89586cda..2181c2623fa 100644 --- a/contrib/pg_trgm/trgm_gist.c +++ b/contrib/pg_trgm/trgm_gist.c @@ -191,6 +191,7 @@ gtrgm_consistent(PG_FUNCTION_ARGS) bool res; Size querysize = VARSIZE(query); gtrgm_consistent_cache *cache; + double nlimit; /* * We keep the extracted trigrams in cache, because trigram extraction is @@ -218,6 +219,7 @@ gtrgm_consistent(PG_FUNCTION_ARGS) switch (strategy) { case SimilarityStrategyNumber: + case WordSimilarityStrategyNumber: qtrg = generate_trgm(VARDATA(query), querysize - VARHDRSZ); break; @@ -286,16 +288,23 @@ gtrgm_consistent(PG_FUNCTION_ARGS) switch (strategy) { case SimilarityStrategyNumber: - /* Similarity search is exact */ - *recheck = false; + case WordSimilarityStrategyNumber: + /* Similarity search is exact. Word similarity search is inexact */ + *recheck = (strategy == WordSimilarityStrategyNumber); + nlimit = (strategy == SimilarityStrategyNumber) ? + similarity_threshold : word_similarity_threshold; if (GIST_LEAF(entry)) { /* all leafs contains orig trgm */ - float4 tmpsml = cnt_sml(key, qtrg); + /* + * Prevent gcc optimizing the tmpsml variable using volatile + * keyword. Otherwise comparison of nlimit and tmpsml may give + * wrong results. + */ + float4 volatile tmpsml = cnt_sml(qtrg, key, *recheck); /* strange bug at freebsd 5.2.1 and gcc 3.3.3 */ - res = (*(int *) &tmpsml == *(int *) &similarity_threshold - || tmpsml > similarity_threshold) ? true : false; + res = (*(int *) &tmpsml == *(int *) &nlimit || tmpsml > nlimit); } else if (ISALLTRUE(key)) { /* non-leaf contains signature */ @@ -309,8 +318,7 @@ gtrgm_consistent(PG_FUNCTION_ARGS) if (len == 0) res = false; else - res = (((((float8) count) / ((float8) len))) >= similarity_threshold) - ? true : false; + res = (((((float8) count) / ((float8) len))) >= nlimit); } break; case ILikeStrategyNumber: @@ -428,6 +436,7 @@ gtrgm_distance(PG_FUNCTION_ARGS) StrategyNumber strategy = (StrategyNumber) PG_GETARG_UINT16(2); /* Oid subtype = PG_GETARG_OID(3); */ + bool *recheck = (bool *) PG_GETARG_POINTER(4); TRGM *key = (TRGM *) DatumGetPointer(entry->key); TRGM *qtrg; float8 res; @@ -463,9 +472,17 @@ gtrgm_distance(PG_FUNCTION_ARGS) switch (strategy) { case DistanceStrategyNumber: + case WordDistanceStrategyNumber: + *recheck = strategy == WordDistanceStrategyNumber; if (GIST_LEAF(entry)) { /* all leafs contains orig trgm */ - res = 1.0 - cnt_sml(key, qtrg); + /* + * Prevent gcc optimizing the sml variable using volatile + * keyword. Otherwise res can differ from the + * word_similarity_dist_op() function. + */ + float4 volatile sml = cnt_sml(qtrg, key, *recheck); + res = 1.0 - sml; } else if (ISALLTRUE(key)) { /* all leafs contains orig trgm */ |