diff options
Diffstat (limited to 'src/backend/access/hash/hash.c')
| -rw-r--r-- | src/backend/access/hash/hash.c | 767 |
1 files changed, 399 insertions, 368 deletions
diff --git a/src/backend/access/hash/hash.c b/src/backend/access/hash/hash.c index 89f81fc56a5..e13539c4ad9 100644 --- a/src/backend/access/hash/hash.c +++ b/src/backend/access/hash/hash.c @@ -1,16 +1,16 @@ /*------------------------------------------------------------------------- * * hash.c-- - * Implementation of Margo Seltzer's Hashing package for postgres. + * Implementation of Margo Seltzer's Hashing package for postgres. * * Copyright (c) 1994, Regents of the University of California * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/access/hash/hash.c,v 1.12 1997/01/10 09:46:13 vadim Exp $ + * $Header: /cvsroot/pgsql/src/backend/access/hash/hash.c,v 1.13 1997/09/07 04:37:49 momjian Exp $ * * NOTES - * This file contains only the public interface routines. + * This file contains only the public interface routines. * *------------------------------------------------------------------------- */ @@ -26,452 +26,483 @@ #include <miscadmin.h> #ifndef HAVE_MEMMOVE -# include <regex/utils.h> +#include <regex/utils.h> #else -# include <string.h> +#include <string.h> #endif -bool BuildingHash = false; +bool BuildingHash = false; /* - * hashbuild() -- build a new hash index. + * hashbuild() -- build a new hash index. * - * We use a global variable to record the fact that we're creating - * a new index. This is used to avoid high-concurrency locking, - * since the index won't be visible until this transaction commits - * and since building is guaranteed to be single-threaded. + * We use a global variable to record the fact that we're creating + * a new index. This is used to avoid high-concurrency locking, + * since the index won't be visible until this transaction commits + * and since building is guaranteed to be single-threaded. */ void hashbuild(Relation heap, - Relation index, - int natts, - AttrNumber *attnum, - IndexStrategy istrat, - uint16 pcount, - Datum *params, - FuncIndexInfo *finfo, - PredInfo *predInfo) + Relation index, + int natts, + AttrNumber * attnum, + IndexStrategy istrat, + uint16 pcount, + Datum * params, + FuncIndexInfo * finfo, + PredInfo * predInfo) { - HeapScanDesc hscan; - Buffer buffer; - HeapTuple htup; - IndexTuple itup; - TupleDesc htupdesc, itupdesc; - Datum *attdata; - bool *nulls; - InsertIndexResult res; - int nhtups, nitups; - int i; - HashItem hitem; + HeapScanDesc hscan; + Buffer buffer; + HeapTuple htup; + IndexTuple itup; + TupleDesc htupdesc, + itupdesc; + Datum *attdata; + bool *nulls; + InsertIndexResult res; + int nhtups, + nitups; + int i; + HashItem hitem; + #ifndef OMIT_PARTIAL_INDEX - ExprContext *econtext; - TupleTable tupleTable; - TupleTableSlot *slot; + ExprContext *econtext; + TupleTable tupleTable; + TupleTableSlot *slot; + #endif - Oid hrelid, irelid; - Node *pred, *oldPred; - - /* note that this is a new btree */ - BuildingHash = true; - - pred = predInfo->pred; - oldPred = predInfo->oldPred; - - /* initialize the hash index metadata page (if this is a new index) */ - if (oldPred == NULL) - _hash_metapinit(index); - - /* get tuple descriptors for heap and index relations */ - htupdesc = RelationGetTupleDescriptor(heap); - itupdesc = RelationGetTupleDescriptor(index); - - /* get space for data items that'll appear in the index tuple */ - attdata = (Datum *) palloc(natts * sizeof(Datum)); - nulls = (bool *) palloc(natts * sizeof(bool)); - - /* - * If this is a predicate (partial) index, we will need to evaluate the - * predicate using ExecQual, which requires the current tuple to be in a - * slot of a TupleTable. In addition, ExecQual must have an ExprContext - * referring to that slot. Here, we initialize dummy TupleTable and - * ExprContext objects for this purpose. --Nels, Feb '92 - */ + Oid hrelid, + irelid; + Node *pred, + *oldPred; + + /* note that this is a new btree */ + BuildingHash = true; + + pred = predInfo->pred; + oldPred = predInfo->oldPred; + + /* initialize the hash index metadata page (if this is a new index) */ + if (oldPred == NULL) + _hash_metapinit(index); + + /* get tuple descriptors for heap and index relations */ + htupdesc = RelationGetTupleDescriptor(heap); + itupdesc = RelationGetTupleDescriptor(index); + + /* get space for data items that'll appear in the index tuple */ + attdata = (Datum *) palloc(natts * sizeof(Datum)); + nulls = (bool *) palloc(natts * sizeof(bool)); + + /* + * If this is a predicate (partial) index, we will need to evaluate + * the predicate using ExecQual, which requires the current tuple to + * be in a slot of a TupleTable. In addition, ExecQual must have an + * ExprContext referring to that slot. Here, we initialize dummy + * TupleTable and ExprContext objects for this purpose. --Nels, Feb + * '92 + */ #ifndef OMIT_PARTIAL_INDEX - if (pred != NULL || oldPred != NULL) { - tupleTable = ExecCreateTupleTable(1); - slot = ExecAllocTableSlot(tupleTable); - econtext = makeNode(ExprContext); - FillDummyExprContext(econtext, slot, htupdesc, buffer); - } - else /* quiet the compiler */ + if (pred != NULL || oldPred != NULL) + { + tupleTable = ExecCreateTupleTable(1); + slot = ExecAllocTableSlot(tupleTable); + econtext = makeNode(ExprContext); + FillDummyExprContext(econtext, slot, htupdesc, buffer); + } + else +/* quiet the compiler */ { econtext = NULL; tupleTable = 0; slot = 0; } -#endif /* OMIT_PARTIAL_INDEX */ - - /* start a heap scan */ - hscan = heap_beginscan(heap, 0, NowTimeQual, 0, (ScanKey) NULL); - htup = heap_getnext(hscan, 0, &buffer); - - /* build the index */ - nhtups = nitups = 0; - - for (; HeapTupleIsValid(htup); htup = heap_getnext(hscan, 0, &buffer)) { - - nhtups++; - - /* - * If oldPred != NULL, this is an EXTEND INDEX command, so skip - * this tuple if it was already in the existing partial index - */ - if (oldPred != NULL) { - /*SetSlotContents(slot, htup); */ +#endif /* OMIT_PARTIAL_INDEX */ + + /* start a heap scan */ + hscan = heap_beginscan(heap, 0, NowTimeQual, 0, (ScanKey) NULL); + htup = heap_getnext(hscan, 0, &buffer); + + /* build the index */ + nhtups = nitups = 0; + + for (; HeapTupleIsValid(htup); htup = heap_getnext(hscan, 0, &buffer)) + { + + nhtups++; + + /* + * If oldPred != NULL, this is an EXTEND INDEX command, so skip + * this tuple if it was already in the existing partial index + */ + if (oldPred != NULL) + { + /* SetSlotContents(slot, htup); */ #ifndef OMIT_PARTIAL_INDEX - slot->val = htup; - if (ExecQual((List*)oldPred, econtext) == true) { + slot->val = htup; + if (ExecQual((List *) oldPred, econtext) == true) + { + nitups++; + continue; + } +#endif /* OMIT_PARTIAL_INDEX */ + } + + /* + * Skip this tuple if it doesn't satisfy the partial-index + * predicate + */ + if (pred != NULL) + { +#ifndef OMIT_PARTIAL_INDEX + /* SetSlotContents(slot, htup); */ + slot->val = htup; + if (ExecQual((List *) pred, econtext) == false) + continue; +#endif /* OMIT_PARTIAL_INDEX */ + } + nitups++; - continue; - } -#endif /* OMIT_PARTIAL_INDEX */ + + /* + * For the current heap tuple, extract all the attributes we use + * in this index, and note which are null. + */ + for (i = 1; i <= natts; i++) + { + int attoff; + bool attnull; + + /* + * Offsets are from the start of the tuple, and are + * zero-based; indices are one-based. The next call returns i + * - 1. That's data hiding for you. + */ + + /* attoff = i - 1 */ + attoff = AttrNumberGetAttrOffset(i); + + /* + * below, attdata[attoff] set to equal some datum & attnull is + * changed to indicate whether or not the attribute is null + * for this tuple + */ + attdata[attoff] = GetIndexValue(htup, + htupdesc, + attoff, + attnum, + finfo, + &attnull, + buffer); + nulls[attoff] = (attnull ? 'n' : ' '); + } + + /* form an index tuple and point it at the heap tuple */ + itup = index_formtuple(itupdesc, attdata, nulls); + + /* + * If the single index key is null, we don't insert it into the + * index. Hash tables support scans on '='. Relational algebra + * says that A = B returns null if either A or B is null. This + * means that no qualification used in an index scan could ever + * return true on a null attribute. It also means that indices + * can't be used by ISNULL or NOTNULL scans, but that's an + * artifact of the strategy map architecture chosen in 1986, not + * of the way nulls are handled here. + */ + + if (itup->t_info & INDEX_NULL_MASK) + { + pfree(itup); + continue; + } + + itup->t_tid = htup->t_ctid; + hitem = _hash_formitem(itup); + res = _hash_doinsert(index, hitem); + pfree(hitem); + pfree(itup); + pfree(res); } - - /* Skip this tuple if it doesn't satisfy the partial-index predicate */ - if (pred != NULL) { + + /* okay, all heap tuples are indexed */ + heap_endscan(hscan); + + if (pred != NULL || oldPred != NULL) + { #ifndef OMIT_PARTIAL_INDEX - /*SetSlotContents(slot, htup); */ - slot->val = htup; - if (ExecQual((List*)pred, econtext) == false) - continue; -#endif /* OMIT_PARTIAL_INDEX */ -} - - nitups++; - - /* - * For the current heap tuple, extract all the attributes - * we use in this index, and note which are null. - */ - for (i = 1; i <= natts; i++) { - int attoff; - bool attnull; - - /* - * Offsets are from the start of the tuple, and are - * zero-based; indices are one-based. The next call - * returns i - 1. That's data hiding for you. - */ - - /* attoff = i - 1 */ - attoff = AttrNumberGetAttrOffset(i); - - /* below, attdata[attoff] set to equal some datum & - * attnull is changed to indicate whether or not the attribute - * is null for this tuple - */ - attdata[attoff] = GetIndexValue(htup, - htupdesc, - attoff, - attnum, - finfo, - &attnull, - buffer); - nulls[attoff] = (attnull ? 'n' : ' '); + ExecDestroyTupleTable(tupleTable, true); + pfree(econtext); +#endif /* OMIT_PARTIAL_INDEX */ } - - /* form an index tuple and point it at the heap tuple */ - itup = index_formtuple(itupdesc, attdata, nulls); - + /* - * If the single index key is null, we don't insert it into - * the index. Hash tables support scans on '='. - * Relational algebra says that A = B - * returns null if either A or B is null. This - * means that no qualification used in an index scan could ever - * return true on a null attribute. It also means that indices - * can't be used by ISNULL or NOTNULL scans, but that's an - * artifact of the strategy map architecture chosen in 1986, not - * of the way nulls are handled here. + * Since we just counted the tuples in the heap, we update its stats + * in pg_class to guarantee that the planner takes advantage of the + * index we just created. Finally, only update statistics during + * normal index definitions, not for indices on system catalogs + * created during bootstrap processing. We must close the relations + * before updatings statistics to guarantee that the relcache entries + * are flushed when we increment the command counter in UpdateStats(). */ - - if (itup->t_info & INDEX_NULL_MASK) { - pfree(itup); - continue; - } - - itup->t_tid = htup->t_ctid; - hitem = _hash_formitem(itup); - res = _hash_doinsert(index, hitem); - pfree(hitem); - pfree(itup); - pfree(res); - } - - /* okay, all heap tuples are indexed */ - heap_endscan(hscan); - - if (pred != NULL || oldPred != NULL) { -#ifndef OMIT_PARTIAL_INDEX - ExecDestroyTupleTable(tupleTable, true); - pfree(econtext); -#endif /* OMIT_PARTIAL_INDEX */ - } - - /* - * Since we just counted the tuples in the heap, we update its - * stats in pg_class to guarantee that the planner takes advantage - * of the index we just created. Finally, only update statistics - * during normal index definitions, not for indices on system catalogs - * created during bootstrap processing. We must close the relations - * before updatings statistics to guarantee that the relcache entries - * are flushed when we increment the command counter in UpdateStats(). - */ - if (IsNormalProcessingMode()) + if (IsNormalProcessingMode()) { - hrelid = heap->rd_id; - irelid = index->rd_id; - heap_close(heap); - index_close(index); - UpdateStats(hrelid, nhtups, true); - UpdateStats(irelid, nitups, false); - if (oldPred != NULL) { - if (nitups == nhtups) pred = NULL; - UpdateIndexPredicate(irelid, oldPred, pred); - } + hrelid = heap->rd_id; + irelid = index->rd_id; + heap_close(heap); + index_close(index); + UpdateStats(hrelid, nhtups, true); + UpdateStats(irelid, nitups, false); + if (oldPred != NULL) + { + if (nitups == nhtups) + pred = NULL; + UpdateIndexPredicate(irelid, oldPred, pred); + } } - - /* be tidy */ - pfree(nulls); - pfree(attdata); - - /* all done */ - BuildingHash = false; + + /* be tidy */ + pfree(nulls); + pfree(attdata); + + /* all done */ + BuildingHash = false; } /* - * hashinsert() -- insert an index tuple into a hash table. + * hashinsert() -- insert an index tuple into a hash table. * - * Hash on the index tuple's key, find the appropriate location - * for the new tuple, put it there, and return an InsertIndexResult - * to the caller. + * Hash on the index tuple's key, find the appropriate location + * for the new tuple, put it there, and return an InsertIndexResult + * to the caller. */ InsertIndexResult -hashinsert(Relation rel, Datum *datum, char *nulls, ItemPointer ht_ctid, Relation heapRel) +hashinsert(Relation rel, Datum * datum, char *nulls, ItemPointer ht_ctid, Relation heapRel) { - HashItem hitem; - IndexTuple itup; - InsertIndexResult res; - - - /* generate an index tuple */ - itup = index_formtuple(RelationGetTupleDescriptor(rel), datum, nulls); - itup->t_tid = *ht_ctid; - - if (itup->t_info & INDEX_NULL_MASK) - return ((InsertIndexResult) NULL); - - hitem = _hash_formitem(itup); - - res = _hash_doinsert(rel, hitem); - - pfree(hitem); - pfree(itup); - - return (res); + HashItem hitem; + IndexTuple itup; + InsertIndexResult res; + + + /* generate an index tuple */ + itup = index_formtuple(RelationGetTupleDescriptor(rel), datum, nulls); + itup->t_tid = *ht_ctid; + + if (itup->t_info & INDEX_NULL_MASK) + return ((InsertIndexResult) NULL); + + hitem = _hash_formitem(itup); + + res = _hash_doinsert(rel, hitem); + + pfree(hitem); + pfree(itup); + + return (res); } /* - * hashgettuple() -- Get the next tuple in the scan. + * hashgettuple() -- Get the next tuple in the scan. */ -char * +char * hashgettuple(IndexScanDesc scan, ScanDirection dir) { - RetrieveIndexResult res; - - /* - * If we've already initialized this scan, we can just advance it - * in the appropriate direction. If we haven't done so yet, we - * call a routine to get the first item in the scan. - */ - - if (ItemPointerIsValid(&(scan->currentItemData))) - res = _hash_next(scan, dir); - else - res = _hash_first(scan, dir); - - return ((char *) res); + RetrieveIndexResult res; + + /* + * If we've already initialized this scan, we can just advance it in + * the appropriate direction. If we haven't done so yet, we call a + * routine to get the first item in the scan. + */ + + if (ItemPointerIsValid(&(scan->currentItemData))) + res = _hash_next(scan, dir); + else + res = _hash_first(scan, dir); + + return ((char *) res); } /* - * hashbeginscan() -- start a scan on a hash index + * hashbeginscan() -- start a scan on a hash index */ -char * +char * hashbeginscan(Relation rel, - bool fromEnd, - uint16 keysz, - ScanKey scankey) + bool fromEnd, + uint16 keysz, + ScanKey scankey) { - IndexScanDesc scan; - HashScanOpaque so; - - scan = RelationGetIndexScan(rel, fromEnd, keysz, scankey); - so = (HashScanOpaque) palloc(sizeof(HashScanOpaqueData)); - so->hashso_curbuf = so->hashso_mrkbuf = InvalidBuffer; - scan->opaque = so; - scan->flags = 0x0; - - /* register scan in case we change pages it's using */ - _hash_regscan(scan); - - return ((char *) scan); + IndexScanDesc scan; + HashScanOpaque so; + + scan = RelationGetIndexScan(rel, fromEnd, keysz, scankey); + so = (HashScanOpaque) palloc(sizeof(HashScanOpaqueData)); + so->hashso_curbuf = so->hashso_mrkbuf = InvalidBuffer; + scan->opaque = so; + scan->flags = 0x0; + + /* register scan in case we change pages it's using */ + _hash_regscan(scan); + + return ((char *) scan); } /* - * hashrescan() -- rescan an index relation + * hashrescan() -- rescan an index relation */ void hashrescan(IndexScanDesc scan, bool fromEnd, ScanKey scankey) { - ItemPointer iptr; - HashScanOpaque so; - - so = (HashScanOpaque) scan->opaque; - - /* we hold a read lock on the current page in the scan */ - if (ItemPointerIsValid(iptr = &(scan->currentItemData))) { - _hash_relbuf(scan->relation, so->hashso_curbuf, HASH_READ); - so->hashso_curbuf = InvalidBuffer; - ItemPointerSetInvalid(iptr); - } - if (ItemPointerIsValid(iptr = &(scan->currentMarkData))) { - _hash_relbuf(scan->relation, so->hashso_mrkbuf, HASH_READ); - so->hashso_mrkbuf = InvalidBuffer; - ItemPointerSetInvalid(iptr); - } - - /* reset the scan key */ - if (scan->numberOfKeys > 0) { - memmove(scan->keyData, - scankey, - scan->numberOfKeys * sizeof(ScanKeyData)); - } + ItemPointer iptr; + HashScanOpaque so; + + so = (HashScanOpaque) scan->opaque; + + /* we hold a read lock on the current page in the scan */ + if (ItemPointerIsValid(iptr = &(scan->currentItemData))) + { + _hash_relbuf(scan->relation, so->hashso_curbuf, HASH_READ); + so->hashso_curbuf = InvalidBuffer; + ItemPointerSetInvalid(iptr); + } + if (ItemPointerIsValid(iptr = &(scan->currentMarkData))) + { + _hash_relbuf(scan->relation, so->hashso_mrkbuf, HASH_READ); + so->hashso_mrkbuf = InvalidBuffer; + ItemPointerSetInvalid(iptr); + } + + /* reset the scan key */ + if (scan->numberOfKeys > 0) + { + memmove(scan->keyData, + scankey, + scan->numberOfKeys * sizeof(ScanKeyData)); + } } /* - * hashendscan() -- close down a scan + * hashendscan() -- close down a scan */ void hashendscan(IndexScanDesc scan) { - - ItemPointer iptr; - HashScanOpaque so; - - so = (HashScanOpaque) scan->opaque; - - /* release any locks we still hold */ - if (ItemPointerIsValid(iptr = &(scan->currentItemData))) { - _hash_relbuf(scan->relation, so->hashso_curbuf, HASH_READ); - so->hashso_curbuf = InvalidBuffer; - ItemPointerSetInvalid(iptr); - } - - if (ItemPointerIsValid(iptr = &(scan->currentMarkData))) { - if (BufferIsValid(so->hashso_mrkbuf)) - _hash_relbuf(scan->relation, so->hashso_mrkbuf, HASH_READ); - so->hashso_mrkbuf = InvalidBuffer; - ItemPointerSetInvalid(iptr); - } - - /* don't need scan registered anymore */ - _hash_dropscan(scan); - - /* be tidy */ - pfree (scan->opaque); + + ItemPointer iptr; + HashScanOpaque so; + + so = (HashScanOpaque) scan->opaque; + + /* release any locks we still hold */ + if (ItemPointerIsValid(iptr = &(scan->currentItemData))) + { + _hash_relbuf(scan->relation, so->hashso_curbuf, HASH_READ); + so->hashso_curbuf = InvalidBuffer; + ItemPointerSetInvalid(iptr); + } + + if (ItemPointerIsValid(iptr = &(scan->currentMarkData))) + { + if (BufferIsValid(so->hashso_mrkbuf)) + _hash_relbuf(scan->relation, so->hashso_mrkbuf, HASH_READ); + so->hashso_mrkbuf = InvalidBuffer; + ItemPointerSetInvalid(iptr); + } + + /* don't need scan registered anymore */ + _hash_dropscan(scan); + + /* be tidy */ + pfree(scan->opaque); } /* - * hashmarkpos() -- save current scan position + * hashmarkpos() -- save current scan position * */ void hashmarkpos(IndexScanDesc scan) { - ItemPointer iptr; - HashScanOpaque so; - - /* see if we ever call this code. if we do, then so_mrkbuf a - * useful element in the scan->opaque structure. if this procedure - * is never called, so_mrkbuf should be removed from the scan->opaque - * structure. - */ - elog(NOTICE, "Hashmarkpos() called."); - - so = (HashScanOpaque) scan->opaque; - - /* release lock on old marked data, if any */ - if (ItemPointerIsValid(iptr = &(scan->currentMarkData))) { - _hash_relbuf(scan->relation, so->hashso_mrkbuf, HASH_READ); - so->hashso_mrkbuf = InvalidBuffer; - ItemPointerSetInvalid(iptr); - } - - /* bump lock on currentItemData and copy to currentMarkData */ - if (ItemPointerIsValid(&(scan->currentItemData))) { - so->hashso_mrkbuf = _hash_getbuf(scan->relation, - BufferGetBlockNumber(so->hashso_curbuf), - HASH_READ); - scan->currentMarkData = scan->currentItemData; - } + ItemPointer iptr; + HashScanOpaque so; + + /* + * see if we ever call this code. if we do, then so_mrkbuf a useful + * element in the scan->opaque structure. if this procedure is never + * called, so_mrkbuf should be removed from the scan->opaque + * structure. + */ + elog(NOTICE, "Hashmarkpos() called."); + + so = (HashScanOpaque) scan->opaque; + + /* release lock on old marked data, if any */ + if (ItemPointerIsValid(iptr = &(scan->currentMarkData))) + { + _hash_relbuf(scan->relation, so->hashso_mrkbuf, HASH_READ); + so->hashso_mrkbuf = InvalidBuffer; + ItemPointerSetInvalid(iptr); + } + + /* bump lock on currentItemData and copy to currentMarkData */ + if (ItemPointerIsValid(&(scan->currentItemData))) + { + so->hashso_mrkbuf = _hash_getbuf(scan->relation, + BufferGetBlockNumber(so->hashso_curbuf), + HASH_READ); + scan->currentMarkData = scan->currentItemData; + } } /* - * hashrestrpos() -- restore scan to last saved position + * hashrestrpos() -- restore scan to last saved position */ void hashrestrpos(IndexScanDesc scan) { - ItemPointer iptr; - HashScanOpaque so; - - /* see if we ever call this code. if we do, then so_mrkbuf a - * useful element in the scan->opaque structure. if this procedure - * is never called, so_mrkbuf should be removed from the scan->opaque - * structure. - */ - elog(NOTICE, "Hashrestrpos() called."); - - so = (HashScanOpaque) scan->opaque; - - /* release lock on current data, if any */ - if (ItemPointerIsValid(iptr = &(scan->currentItemData))) { - _hash_relbuf(scan->relation, so->hashso_curbuf, HASH_READ); - so->hashso_curbuf = InvalidBuffer; - ItemPointerSetInvalid(iptr); - } - - /* bump lock on currentMarkData and copy to currentItemData */ - if (ItemPointerIsValid(&(scan->currentMarkData))) { - so->hashso_curbuf = - _hash_getbuf(scan->relation, - BufferGetBlockNumber(so->hashso_mrkbuf), - HASH_READ); - - scan->currentItemData = scan->currentMarkData; - } + ItemPointer iptr; + HashScanOpaque so; + + /* + * see if we ever call this code. if we do, then so_mrkbuf a useful + * element in the scan->opaque structure. if this procedure is never + * called, so_mrkbuf should be removed from the scan->opaque + * structure. + */ + elog(NOTICE, "Hashrestrpos() called."); + + so = (HashScanOpaque) scan->opaque; + + /* release lock on current data, if any */ + if (ItemPointerIsValid(iptr = &(scan->currentItemData))) + { + _hash_relbuf(scan->relation, so->hashso_curbuf, HASH_READ); + so->hashso_curbuf = InvalidBuffer; + ItemPointerSetInvalid(iptr); + } + + /* bump lock on currentMarkData and copy to currentItemData */ + if (ItemPointerIsValid(&(scan->currentMarkData))) + { + so->hashso_curbuf = + _hash_getbuf(scan->relation, + BufferGetBlockNumber(so->hashso_mrkbuf), + HASH_READ); + + scan->currentItemData = scan->currentMarkData; + } } /* stubs */ void hashdelete(Relation rel, ItemPointer tid) { - /* adjust any active scans that will be affected by this deletion */ - _hash_adjscans(rel, tid); - - /* delete the data from the page */ - _hash_pagedel(rel, tid); -} + /* adjust any active scans that will be affected by this deletion */ + _hash_adjscans(rel, tid); + /* delete the data from the page */ + _hash_pagedel(rel, tid); +} |