diff options
Diffstat (limited to 'src/backend/access/gin')
| -rw-r--r-- | src/backend/access/gin/ginarrayproc.c | 41 | ||||
| -rw-r--r-- | src/backend/access/gin/ginget.c | 67 |
2 files changed, 76 insertions, 32 deletions
diff --git a/src/backend/access/gin/ginarrayproc.c b/src/backend/access/gin/ginarrayproc.c index c453cda525..c85399d632 100644 --- a/src/backend/access/gin/ginarrayproc.c +++ b/src/backend/access/gin/ginarrayproc.c @@ -8,7 +8,7 @@ * Portions Copyright (c) 1994, Regents of the University of California * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/access/gin/ginarrayproc.c,v 1.12 2008/01/01 19:45:46 momjian Exp $ + * $PostgreSQL: pgsql/src/backend/access/gin/ginarrayproc.c,v 1.13 2008/04/14 17:05:33 tgl Exp $ *------------------------------------------------------------------------- */ #include "postgres.h" @@ -95,8 +95,9 @@ ginarrayconsistent(PG_FUNCTION_ARGS) bool *check = (bool *) PG_GETARG_POINTER(0); StrategyNumber strategy = PG_GETARG_UINT16(1); ArrayType *query = PG_GETARG_ARRAYTYPE_P(2); - int res, - i, + bool *recheck = (bool *) PG_GETARG_POINTER(3); + bool res; + int i, nentries; /* ARRAYCHECK was already done by previous ginarrayextract call */ @@ -104,25 +105,51 @@ ginarrayconsistent(PG_FUNCTION_ARGS) switch (strategy) { case GinOverlapStrategy: + /* result is not lossy */ + *recheck = false; + /* at least one element in check[] is true, so result = true */ + res = true; + break; case GinContainedStrategy: + /* we will need recheck */ + *recheck = true; /* at least one element in check[] is true, so result = true */ - res = TRUE; + res = true; break; case GinContainsStrategy: + /* result is not lossy */ + *recheck = false; + /* must have all elements in check[] true */ + nentries = ArrayGetNItems(ARR_NDIM(query), ARR_DIMS(query)); + res = true; + for (i = 0; i < nentries; i++) + { + if (!check[i]) + { + res = false; + break; + } + } + break; case GinEqualStrategy: + /* we will need recheck */ + *recheck = true; + /* must have all elements in check[] true */ nentries = ArrayGetNItems(ARR_NDIM(query), ARR_DIMS(query)); - res = TRUE; + res = true; for (i = 0; i < nentries; i++) + { if (!check[i]) { - res = FALSE; + res = false; break; } + } break; default: elog(ERROR, "ginarrayconsistent: unknown strategy number: %d", strategy); - res = FALSE; + res = false; } PG_RETURN_BOOL(res); diff --git a/src/backend/access/gin/ginget.c b/src/backend/access/gin/ginget.c index af38717340..26abaa76af 100644 --- a/src/backend/access/gin/ginget.c +++ b/src/backend/access/gin/ginget.c @@ -8,7 +8,7 @@ * Portions Copyright (c) 1994, Regents of the University of California * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/access/gin/ginget.c,v 1.12 2008/04/13 19:18:13 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/access/gin/ginget.c,v 1.13 2008/04/14 17:05:33 tgl Exp $ *------------------------------------------------------------------------- */ @@ -343,10 +343,12 @@ entryGetItem(Relation index, GinScanEntry entry) /* * Sets key->curItem to new found heap item pointer for one scan key - * returns isFinished! + * Returns isFinished, ie TRUE means we did NOT get a new item pointer! + * Also, *keyrecheck is set true if recheck is needed for this scan key. */ static bool -keyGetItem(Relation index, GinState *ginstate, MemoryContext tempCtx, GinScanKey key) +keyGetItem(Relation index, GinState *ginstate, MemoryContext tempCtx, + GinScanKey key, bool *keyrecheck) { uint32 i; GinScanEntry entry; @@ -391,31 +393,36 @@ keyGetItem(Relation index, GinState *ginstate, MemoryContext tempCtx, GinScanKey return TRUE; } - if (key->nentries == 1) - { - /* we can do not call consistentFn !! */ - key->entryRes[0] = TRUE; - return FALSE; - } + /* + * if key->nentries == 1 then the consistentFn should always succeed, + * but we must call it anyway to find out the recheck status. + */ /* setting up array for consistentFn */ for (i = 0; i < key->nentries; i++) { entry = key->scanEntry + i; - if (entry->isFinished == FALSE && compareItemPointers(&entry->curItem, &key->curItem) == 0) + if (entry->isFinished == FALSE && + compareItemPointers(&entry->curItem, &key->curItem) == 0) key->entryRes[i] = TRUE; else key->entryRes[i] = FALSE; } + /* + * Initialize *keyrecheck in case the consistentFn doesn't know it + * should set it. The safe assumption in that case is to force + * recheck. + */ + *keyrecheck = true; + oldCtx = MemoryContextSwitchTo(tempCtx); - res = DatumGetBool(FunctionCall3( - &ginstate->consistentFn, + res = DatumGetBool(FunctionCall4(&ginstate->consistentFn, PointerGetDatum(key->entryRes), UInt16GetDatum(key->strategy), - key->query - )); + key->query, + PointerGetDatum(keyrecheck))); MemoryContextSwitchTo(oldCtx); MemoryContextReset(tempCtx); } while (!res); @@ -430,24 +437,32 @@ keyGetItem(Relation index, GinState *ginstate, MemoryContext tempCtx, GinScanKey static bool scanGetItem(IndexScanDesc scan, ItemPointerData *item, bool *recheck) { - uint32 i; GinScanOpaque so = (GinScanOpaque) scan->opaque; - - /* XXX for the moment, treat all GIN operators as lossy */ - *recheck = true; + uint32 i; + bool keyrecheck; + + /* + * We return recheck = true if any of the keyGetItem calls return + * keyrecheck = true. Note that because the second loop might advance + * some keys, this could theoretically be too conservative. In practice + * though, we expect that a consistentFn's recheck result will depend + * only on the operator and the query, so for any one key it should + * stay the same regardless of advancing to new items. So it's not + * worth working harder. + */ + *recheck = false; ItemPointerSetMin(item); for (i = 0; i < so->nkeys; i++) { GinScanKey key = so->keys + i; - if (keyGetItem(scan->indexRelation, &so->ginstate, so->tempCtx, key) == FALSE) - { - if (compareItemPointers(item, &key->curItem) < 0) - *item = key->curItem; - } - else + if (keyGetItem(scan->indexRelation, &so->ginstate, so->tempCtx, + key, &keyrecheck)) return FALSE; /* finished one of keys */ + if (compareItemPointers(item, &key->curItem) < 0) + *item = key->curItem; + *recheck |= keyrecheck; } for (i = 1; i <= so->nkeys; i++) @@ -462,8 +477,10 @@ scanGetItem(IndexScanDesc scan, ItemPointerData *item, bool *recheck) break; else if (cmp > 0) { - if (keyGetItem(scan->indexRelation, &so->ginstate, so->tempCtx, key) == TRUE) + if (keyGetItem(scan->indexRelation, &so->ginstate, so->tempCtx, + key, &keyrecheck)) return FALSE; /* finished one of keys */ + *recheck |= keyrecheck; } else { /* returns to begin */ |