Do not fallback to AND for FTS phrase operator.

If there is no positional information of lexemes then phrase operator will not
fallback to AND operator. This change makes needing to modify TS_execute()
interface, because somewhere (in indexes, for example) positional information
is unaccesible and in this cases we need to force fallback to AND.

Per discussion c19fcfec308e6ccd952cdde9e648b505@mail.gmail.com

diff --git a/src/backend/utils/adt/tsginidx.c b/src/backend/utils/adt/tsginidx.c
index b096329143348145de45a5ff043fecfb489350f8..c953f531ff73f865bf0bd658b566e9c6eecbee69 100644 (file)
--- a/src/backend/utils/adt/tsginidx.c
+++ b/src/backend/utils/adt/tsginidx.c
@@ -308,7 +308,7 @@ gin_tsquery_consistent(PG_FUNCTION_ARGS)
 
        res = TS_execute(GETQUERY(query),
                         &gcv,
-                        true,
+                        TS_EXEC_CALC_NOT | TS_EXEC_PHRASE_AS_AND,
                         checkcondition_gin);
    }
 

diff --git a/src/backend/utils/adt/tsgistidx.c b/src/backend/utils/adt/tsgistidx.c
index cdd5d43fce5f33c3ee9ab013fcc0a0cf16b612fb..6cdfb13f6d12221e309bc536a1ba71235141f75b 100644 (file)
--- a/src/backend/utils/adt/tsgistidx.c
+++ b/src/backend/utils/adt/tsgistidx.c
@@ -361,7 +361,8 @@ gtsvector_consistent(PG_FUNCTION_ARGS)
 
        PG_RETURN_BOOL(TS_execute(
                                  GETQUERY(query),
-                                 (void *) GETSIGN(key), false,
+                                 (void *) GETSIGN(key),
+                                 TS_EXEC_PHRASE_AS_AND,
                                  checkcondition_bit
                                  ));
    }
@@ -373,7 +374,8 @@ gtsvector_consistent(PG_FUNCTION_ARGS)
        chkval.arre = chkval.arrb + ARRNELEM(key);
        PG_RETURN_BOOL(TS_execute(
                                  GETQUERY(query),
-                                 (void *) &chkval, true,
+                                 (void *) &chkval,
+                                 TS_EXEC_PHRASE_AS_AND | TS_EXEC_CALC_NOT,
                                  checkcondition_arr
                                  ));
    }

diff --git a/src/backend/utils/adt/tsrank.c b/src/backend/utils/adt/tsrank.c
index 32023821b3fe1b92cc33633a55b96fcb3f07d49d..d887a14d057f404a098e306e7bfdd5586cb8af36 100644 (file)
--- a/src/backend/utils/adt/tsrank.c
+++ b/src/backend/utils/adt/tsrank.c
@@ -662,7 +662,8 @@ Cover(DocRepresentation *doc, int len, QueryRepresentation *qr, CoverExt *ext)
    {
        fillQueryRepresentationData(qr, ptr);
 
-       if (TS_execute(GETQUERY(qr->query), (void *) qr, false, checkcondition_QueryOperand))
+       if (TS_execute(GETQUERY(qr->query), (void *) qr,
+                      TS_EXEC_EMPTY, checkcondition_QueryOperand))
        {
            if (WEP_GETPOS(ptr->pos) > ext->q)
            {
@@ -691,7 +692,8 @@ Cover(DocRepresentation *doc, int len, QueryRepresentation *qr, CoverExt *ext)
         */
        fillQueryRepresentationData(qr, ptr);
 
-       if (TS_execute(GETQUERY(qr->query), (void *) qr, true, checkcondition_QueryOperand))
+       if (TS_execute(GETQUERY(qr->query), (void *) qr,
+                      TS_EXEC_CALC_NOT, checkcondition_QueryOperand))
        {
            if (WEP_GETPOS(ptr->pos) < ext->p)
            {

diff --git a/src/backend/utils/adt/tsvector_op.c b/src/backend/utils/adt/tsvector_op.c
index 04718829a0b960afaa560969e6ce22da6956c49c..242b7e137b727ecd099f421231bbb904e45ed131 100644 (file)
--- a/src/backend/utils/adt/tsvector_op.c
+++ b/src/backend/utils/adt/tsvector_op.c
@@ -1360,7 +1360,7 @@ checkcondition_str(void *checkval, QueryOperand *val, ExecPhraseData *data)
  */
 static bool
 TS_phrase_execute(QueryItem *curitem,
-                 void *checkval, bool calcnot, ExecPhraseData *data,
+                 void *checkval, uint32 flags, ExecPhraseData *data,
                  bool (*chkcond) (void *, QueryOperand *, ExecPhraseData *))
 {
    /* since this function recurses, it could be driven to stack overflow */
@@ -1382,18 +1382,19 @@ TS_phrase_execute(QueryItem *curitem,
        Assert(curitem->qoperator.oper == OP_PHRASE);
 
        if (!TS_phrase_execute(curitem + curitem->qoperator.left,
-                              checkval, calcnot, &Ldata, chkcond))
+                              checkval, flags, &Ldata, chkcond))
            return false;
 
-       if (!TS_phrase_execute(curitem + 1, checkval, calcnot, &Rdata, chkcond))
+       if (!TS_phrase_execute(curitem + 1, checkval, flags, &Rdata, chkcond))
            return false;
 
        /*
         * if at least one of the operands has no position information,
-        * fallback to AND operation.
+        * then return false. But if TS_EXEC_PHRASE_AS_AND flag is set then
+        * we return true as it is a AND operation
         */
        if (Ldata.npos == 0 || Rdata.npos == 0)
-           return true;
+           return (flags & TS_EXEC_PHRASE_AS_AND) ? true : false;
 
        /*
         * Result of the operation is a list of the corresponding positions of
@@ -1498,13 +1499,11 @@ TS_phrase_execute(QueryItem *curitem,
  * chkcond is a callback function used to evaluate each VAL node in the query.
  * checkval can be used to pass information to the callback. TS_execute doesn't
  * do anything with it.
- * if calcnot is false, NOT expressions are always evaluated to be true. This
- * is used in ranking.
  * It believes that ordinary operators are always closier to root than phrase
  * operator, so, TS_execute() may not take care of lexeme's position at all.
  */
 bool
-TS_execute(QueryItem *curitem, void *checkval, bool calcnot,
+TS_execute(QueryItem *curitem, void *checkval, uint32 flags,
    bool (*chkcond) (void *checkval, QueryOperand *val, ExecPhraseData *data))
 {
    /* since this function recurses, it could be driven to stack overflow */
@@ -1517,25 +1516,29 @@ TS_execute(QueryItem *curitem, void *checkval, bool calcnot,
    switch (curitem->qoperator.oper)
    {
        case OP_NOT:
-           if (calcnot)
-               return !TS_execute(curitem + 1, checkval, calcnot, chkcond);
+           if (flags & TS_EXEC_CALC_NOT)
+               return !TS_execute(curitem + 1, checkval, flags, chkcond);
            else
                return true;
 
        case OP_AND:
-           if (TS_execute(curitem + curitem->qoperator.left, checkval, calcnot, chkcond))
-               return TS_execute(curitem + 1, checkval, calcnot, chkcond);
+           if (TS_execute(curitem + curitem->qoperator.left, checkval, flags, chkcond))
+               return TS_execute(curitem + 1, checkval, flags, chkcond);
            else
                return false;
 
        case OP_OR:
-           if (TS_execute(curitem + curitem->qoperator.left, checkval, calcnot, chkcond))
+           if (TS_execute(curitem + curitem->qoperator.left, checkval, flags, chkcond))
                return true;
            else
-               return TS_execute(curitem + 1, checkval, calcnot, chkcond);
+               return TS_execute(curitem + 1, checkval, flags, chkcond);
 
        case OP_PHRASE:
-           return TS_phrase_execute(curitem, checkval, calcnot, NULL, chkcond);
+           /*
+            * do not check TS_EXEC_PHRASE_AS_AND here because chkcond()
+            * could do something more if it's called from TS_phrase_execute()
+            */
+           return TS_phrase_execute(curitem, checkval, flags, NULL, chkcond);
 
        default:
            elog(ERROR, "unrecognized operator: %d", curitem->qoperator.oper);
@@ -1633,7 +1636,7 @@ ts_match_vq(PG_FUNCTION_ARGS)
    result = TS_execute(
                        GETQUERY(query),
                        &chkval,
-                       true,
+                       TS_EXEC_CALC_NOT,
                        checkcondition_str
        );
 

diff --git a/src/include/tsearch/ts_utils.h b/src/include/tsearch/ts_utils.h
index e16ddaf72f4d1c24e08ceb3aaa5e2d1f0e96ea98..e09a9c636f961bef1915668d9b71fdcf225f4a4f 100644 (file)
--- a/src/include/tsearch/ts_utils.h
+++ b/src/include/tsearch/ts_utils.h
@@ -111,8 +111,25 @@ typedef struct ExecPhraseData
    WordEntryPos *pos;
 } ExecPhraseData;
 
-extern bool TS_execute(QueryItem *curitem, void *checkval, bool calcnot,
+/*
+ * Evaluates tsquery, flags are followe below
+ */
+extern bool TS_execute(QueryItem *curitem, void *checkval, uint32 flags,
           bool (*chkcond) (void *, QueryOperand *, ExecPhraseData *));
+
+#define TS_EXEC_EMPTY          (0x00)
+/*
+ * if TS_EXEC_CALC_NOT is not set then NOT expression evaluated to be true,
+ * used in cases where NOT cannot be accurately computed (GiST) or
+ * it isn't important (ranking)
+ */
+#define TS_EXEC_CALC_NOT       (0x01)
+/*
+ * Treat OP_PHRASE as OP_AND. Used when posiotional information is not
+ * accessible, like in consistent methods of GIN/GiST indexes
+ */
+#define TS_EXEC_PHRASE_AS_AND  (0x02)
+
 extern bool tsquery_requires_match(QueryItem *curitem);
 
 /*

diff --git a/src/test/regress/expected/tsearch.out b/src/test/regress/expected/tsearch.out
index 2c3aa1a2937fb746fd3dcba4b67fc0ed267e2038..3a13ad985ff8eda8f450ad8a26061a765e78215a 100644 (file)
--- a/src/test/regress/expected/tsearch.out
+++ b/src/test/regress/expected/tsearch.out
@@ -1459,13 +1459,14 @@ select * from pendtest where 'ipi:*'::tsquery @@ ts;
 
 --check OP_PHRASE on index
 create temp table phrase_index_test(fts tsvector);
-insert into phrase_index_test values('A fat cat has just eaten a rat.');
+insert into phrase_index_test values ('A fat cat has just eaten a rat.');
+insert into phrase_index_test values (to_tsvector('english', 'A fat cat has just eaten a rat.'));
 create index phrase_index_test_idx on phrase_index_test using gin(fts);
 set enable_seqscan = off;
 select * from phrase_index_test where fts @@ phraseto_tsquery('english', 'fat cat');
-                       fts                       
--------------------------------------------------
- 'A' 'a' 'cat' 'eaten' 'fat' 'has' 'just' 'rat.'
+                fts                
+-----------------------------------
+ 'cat':3 'eaten':6 'fat':2 'rat':8
 (1 row)
 
 set enable_seqscan = on;

diff --git a/src/test/regress/sql/tsearch.sql b/src/test/regress/sql/tsearch.sql
index 34b46fa32433bd69c91c70123bcff3bfebfc032c..5f3d335fc393c724e297d79f576193315b5df8a7 100644 (file)
--- a/src/test/regress/sql/tsearch.sql
+++ b/src/test/regress/sql/tsearch.sql
@@ -482,7 +482,8 @@ select * from pendtest where 'ipi:*'::tsquery @@ ts;
 
 --check OP_PHRASE on index
 create temp table phrase_index_test(fts tsvector);
-insert into phrase_index_test values('A fat cat has just eaten a rat.');
+insert into phrase_index_test values ('A fat cat has just eaten a rat.');
+insert into phrase_index_test values (to_tsvector('english', 'A fat cat has just eaten a rat.'));
 create index phrase_index_test_idx on phrase_index_test using gin(fts);
 set enable_seqscan = off;
 select * from phrase_index_test where fts @@ phraseto_tsquery('english', 'fat cat');