Update contrib/hstore for new GIN extractQuery API.

In particular, make hstore @> '' succeed for all hstores, likewise
hstore ?& '{}'.  Previously the results were inconsistent and could
depend on whether you were using a GiST index, GIN index, or seqscan.

diff --git a/contrib/hstore/expected/hstore.out b/contrib/hstore/expected/hstore.out
index 19dd299..354fff2 100644 (file)
--- a/contrib/hstore/expected/hstore.out
+++ b/contrib/hstore/expected/hstore.out
@@ -435,7 +435,7 @@ select hstore 'a=>NULL, b=>qq' ?& ARRAY['c','d'];
 select hstore 'a=>NULL, b=>qq' ?& '{}'::text[];
  ?column? 
 ----------
- f
+ t
 (1 row)
 
 -- delete

diff --git a/contrib/hstore/hstore_gin.c b/contrib/hstore/hstore_gin.c
index 8fd3d27..d55674c 100644 (file)
--- a/contrib/hstore/hstore_gin.c
+++ b/contrib/hstore/hstore_gin.c
@@ -10,6 +10,13 @@
 #include "hstore.h"
 
 
+/*
+ * When using a GIN index for hstore, we choose to index both keys and values.
+ * The storage format is "text" values, with K, V, or N prepended to the string
+ * to indicate key, value, or null values.  (As of 9.1 it might be better to
+ * store null values as nulls, but we'll keep it this way for on-disk
+ * compatibility.)
+ */
 #define KEYFLAG                'K'
 #define VALFLAG                'V'
 #define NULLFLAG       'N'
@@ -17,14 +24,17 @@
 PG_FUNCTION_INFO_V1(gin_extract_hstore);
 Datum          gin_extract_hstore(PG_FUNCTION_ARGS);
 
+/* Build an indexable text value */
 static text *
-makeitem(char *str, int len)
+makeitem(char *str, int len, char flag)
 {
        text       *item;
 
        item = (text *) palloc(VARHDRSZ + len + 1);
        SET_VARSIZE(item, VARHDRSZ + len + 1);
 
+       *VARDATA(item) = flag;
+
        if (str && len > 0)
                memcpy(VARDATA(item) + 1, str, len);
 
@@ -50,20 +60,15 @@ gin_extract_hstore(PG_FUNCTION_ARGS)
        {
                text       *item;
 
-               item = makeitem(HS_KEY(hsent, ptr, i), HS_KEYLEN(hsent, i));
-               *VARDATA(item) = KEYFLAG;
+               item = makeitem(HS_KEY(hsent, ptr, i), HS_KEYLEN(hsent, i),
+                                               KEYFLAG);
                entries[2 * i] = PointerGetDatum(item);
 
                if (HS_VALISNULL(hsent, i))
-               {
-                       item = makeitem(NULL, 0);
-                       *VARDATA(item) = NULLFLAG;
-               }
+                       item = makeitem(NULL, 0, NULLFLAG);
                else
-               {
-                       item = makeitem(HS_VAL(hsent, ptr, i), HS_VALLEN(hsent, i));
-                       *VARDATA(item) = VALFLAG;
-               }
+                       item = makeitem(HS_VAL(hsent, ptr, i), HS_VALLEN(hsent, i),
+                                                       VALFLAG);
                entries[2 * i + 1] = PointerGetDatum(item);
        }
 
@@ -76,30 +81,31 @@ Datum               gin_extract_hstore_query(PG_FUNCTION_ARGS);
 Datum
 gin_extract_hstore_query(PG_FUNCTION_ARGS)
 {
+       int32      *nentries = (int32 *) PG_GETARG_POINTER(1);
        StrategyNumber strategy = PG_GETARG_UINT16(2);
+       int32      *searchMode = (int32 *) PG_GETARG_POINTER(6);
+       Datum      *entries;
 
        if (strategy == HStoreContainsStrategyNumber)
        {
-               PG_RETURN_DATUM(DirectFunctionCall2(gin_extract_hstore,
-                                                                                       PG_GETARG_DATUM(0),
-                                                                                       PG_GETARG_DATUM(1)
-                                                                                       ));
+               /* Query is an hstore, so just apply gin_extract_hstore... */
+               entries = (Datum *)
+                       DatumGetPointer(DirectFunctionCall2(gin_extract_hstore,
+                                                                                               PG_GETARG_DATUM(0),
+                                                                                               PointerGetDatum(nentries)));
+               /* ... except that "contains {}" requires a full index scan */
+               if (entries == NULL)
+                       *searchMode = GIN_SEARCH_MODE_ALL;
        }
        else if (strategy == HStoreExistsStrategyNumber)
        {
-               text       *item,
-                                  *query = PG_GETARG_TEXT_PP(0);
-               int32      *nentries = (int32 *) PG_GETARG_POINTER(1);
-               Datum      *entries = NULL;
+               text       *query = PG_GETARG_TEXT_PP(0);
+               text       *item;
 
                *nentries = 1;
                entries = (Datum *) palloc(sizeof(Datum));
-
-               item = makeitem(VARDATA_ANY(query), VARSIZE_ANY_EXHDR(query));
-               *VARDATA(item) = KEYFLAG;
+               item = makeitem(VARDATA_ANY(query), VARSIZE_ANY_EXHDR(query), KEYFLAG);
                entries[0] = PointerGetDatum(item);
-
-               PG_RETURN_POINTER(entries);
        }
        else if (strategy == HStoreExistsAnyStrategyNumber ||
                         strategy == HStoreExistsAllStrategyNumber)
@@ -110,8 +116,6 @@ gin_extract_hstore_query(PG_FUNCTION_ARGS)
                int                     key_count;
                int                     i,
                                        j;
-               int32      *nentries = (int32 *) PG_GETARG_POINTER(1);
-               Datum      *entries = NULL;
                text       *item;
 
                deconstruct_array(query,
@@ -122,21 +126,25 @@ gin_extract_hstore_query(PG_FUNCTION_ARGS)
 
                for (i = 0, j = 0; i < key_count; ++i)
                {
+                       /* Nulls in the array are ignored, cf hstoreArrayToPairs */
                        if (key_nulls[i])
                                continue;
-                       item = makeitem(VARDATA(key_datums[i]), VARSIZE(key_datums[i]) - VARHDRSZ);
-                       *VARDATA(item) = KEYFLAG;
+                       item = makeitem(VARDATA(key_datums[i]), VARSIZE(key_datums[i]) - VARHDRSZ, KEYFLAG);
                        entries[j++] = PointerGetDatum(item);
                }
 
-               *nentries = j ? j : -1;
-
-               PG_RETURN_POINTER(entries);
+               *nentries = j;
+               /* ExistsAll with no keys should match everything */
+               if (j == 0 && strategy == HStoreExistsAllStrategyNumber)
+                       *searchMode = GIN_SEARCH_MODE_ALL;
        }
        else
-               elog(ERROR, "Unsupported strategy number: %d", strategy);
+       {
+               elog(ERROR, "unrecognized strategy number: %d", strategy);
+               entries = NULL;                 /* keep compiler quiet */
+       }
 
-       PG_RETURN_POINTER(NULL);
+       PG_RETURN_POINTER(entries);
 }
 
 PG_FUNCTION_INFO_V1(gin_consistent_hstore);
@@ -154,42 +162,52 @@ gin_consistent_hstore(PG_FUNCTION_ARGS)
        /* Pointer         *extra_data = (Pointer *) PG_GETARG_POINTER(4); */
        bool       *recheck = (bool *) PG_GETARG_POINTER(5);
        bool            res = true;
-
-       *recheck = false;
+       int32           i;
 
        if (strategy == HStoreContainsStrategyNumber)
        {
-               int                     i;
-
                /*
-                * Index lost information about correspondence of keys and values, so
-                * we need recheck (pre-8.4 this is handled at SQL level)
+                * Index doesn't have information about correspondence of keys and
+                * values, so we need recheck.  However, if not all the keys are
+                * present, we can fail at once.
                 */
                *recheck = true;
-               for (i = 0; res && i < nkeys; i++)
-                       if (check[i] == false)
+               for (i = 0; i < nkeys; i++)
+               {
+                       if (!check[i])
+                       {
                                res = false;
+                               break;
+                       }
+               }
        }
        else if (strategy == HStoreExistsStrategyNumber)
        {
-               /* Existence of key is guaranteed */
+               /* Existence of key is guaranteed in default search mode */
+               *recheck = false;
                res = true;
        }
        else if (strategy == HStoreExistsAnyStrategyNumber)
        {
-               /* Existence of key is guaranteed */
+               /* Existence of key is guaranteed in default search mode */
+               *recheck = false;
                res = true;
        }
        else if (strategy == HStoreExistsAllStrategyNumber)
        {
-               int                     i;
-
-               for (i = 0; res && i < nkeys; ++i)
+               /* Testing for all the keys being present gives an exact result */
+               *recheck = false;
+               for (i = 0; i < nkeys; i++)
+               {
                        if (!check[i])
+                       {
                                res = false;
+                               break;
+                       }
+               }
        }
        else
-               elog(ERROR, "Unsupported strategy number: %d", strategy);
+               elog(ERROR, "unrecognized strategy number: %d", strategy);
 
        PG_RETURN_BOOL(res);
 }

diff --git a/contrib/hstore/hstore_op.c b/contrib/hstore/hstore_op.c
index 93d8cbc..cb6200a 100644 (file)
--- a/contrib/hstore/hstore_op.c
+++ b/contrib/hstore/hstore_op.c
@@ -168,14 +168,16 @@ hstore_exists_any(PG_FUNCTION_ARGS)
         * start one entry past the previous "found" entry, or at the lower bound
         * of the last search.
         */
-
-       for (i = 0; !res && i < nkeys; ++i)
+       for (i = 0; i < nkeys; i++)
        {
                int                     idx = hstoreFindKey(hs, &lowbound,
                                                                          key_pairs[i].key, key_pairs[i].keylen);
 
                if (idx >= 0)
+               {
                        res = true;
+                       break;
+               }
        }
 
        PG_RETURN_BOOL(res);
@@ -193,7 +195,7 @@ hstore_exists_all(PG_FUNCTION_ARGS)
        Pairs      *key_pairs = hstoreArrayToPairs(keys, &nkeys);
        int                     i;
        int                     lowbound = 0;
-       bool            res = nkeys ? true : false;
+       bool            res = true;
 
        /*
         * we exploit the fact that the pairs list is already sorted into strictly
@@ -201,14 +203,16 @@ hstore_exists_all(PG_FUNCTION_ARGS)
         * start one entry past the previous "found" entry, or at the lower bound
         * of the last search.
         */
-
-       for (i = 0; res && i < nkeys; ++i)
+       for (i = 0; i < nkeys; i++)
        {
                int                     idx = hstoreFindKey(hs, &lowbound,
                                                                          key_pairs[i].key, key_pairs[i].keylen);
 
                if (idx < 0)
+               {
                        res = false;
+                       break;
+               }
        }
 
        PG_RETURN_BOOL(res);