Create new routines systable_beginscan_ordered, systable_getnext_ordered,

systable_endscan_ordered that have API similar to systable_beginscan etc
(in particular, the passed-in scankeys have heap not index attnums),
but guarantee ordered output, unlike the existing functions.  For the moment
these are just very thin wrappers around index_beginscan/index_getnext/etc.
Someday they might need to get smarter; but for now this is just a code
refactoring exercise to reduce the number of direct callers of index_getnext,
in preparation for changing that function's API.

In passing, remove index_getnext_indexitem, which has been dead code for
quite some time, and will have even less use than that in the presence
of run-time-lossy indexes.
This commit is contained in:
Tom Lane 2008-04-12 23:14:21 +00:00
parent 00832809a0
commit ec498cdcbb
9 changed files with 168 additions and 124 deletions

View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/access/heap/tuptoaster.c,v 1.85 2008/03/26 21:10:37 alvherre Exp $
* $PostgreSQL: pgsql/src/backend/access/heap/tuptoaster.c,v 1.86 2008/04/12 23:14:21 tgl Exp $
*
*
* INTERFACE ROUTINES
@ -1184,7 +1184,9 @@ toast_save_datum(Relation rel, Datum value,
toast_pointer.va_extsize = data_todo;
}
toast_pointer.va_valueid = GetNewOidWithIndex(toastrel, toastidx);
toast_pointer.va_valueid = GetNewOidWithIndex(toastrel,
RelationGetRelid(toastidx),
(AttrNumber) 1);
toast_pointer.va_toastrelid = rel->rd_rel->reltoastrelid;
/*
@ -1273,7 +1275,7 @@ toast_delete_datum(Relation rel, Datum value)
Relation toastrel;
Relation toastidx;
ScanKeyData toastkey;
IndexScanDesc toastscan;
SysScanDesc toastscan;
HeapTuple toasttup;
if (!VARATT_IS_EXTERNAL(attr))
@ -1289,8 +1291,7 @@ toast_delete_datum(Relation rel, Datum value)
toastidx = index_open(toastrel->rd_rel->reltoastidxid, RowExclusiveLock);
/*
* Setup a scan key to fetch from the index by va_valueid (we don't
* particularly care whether we see them in sequence or not)
* Setup a scan key to find chunks with matching va_valueid
*/
ScanKeyInit(&toastkey,
(AttrNumber) 1,
@ -1298,11 +1299,13 @@ toast_delete_datum(Relation rel, Datum value)
ObjectIdGetDatum(toast_pointer.va_valueid));
/*
* Find the chunks by index
* Find all the chunks. (We don't actually care whether we see them in
* sequence or not, but since we've already locked the index we might
* as well use systable_beginscan_ordered.)
*/
toastscan = index_beginscan(toastrel, toastidx,
SnapshotToast, 1, &toastkey);
while ((toasttup = index_getnext(toastscan, ForwardScanDirection)) != NULL)
toastscan = systable_beginscan_ordered(toastrel, toastidx,
SnapshotToast, 1, &toastkey);
while ((toasttup = systable_getnext_ordered(toastscan, ForwardScanDirection)) != NULL)
{
/*
* Have a chunk, delete it
@ -1313,7 +1316,7 @@ toast_delete_datum(Relation rel, Datum value)
/*
* End scan and close relations
*/
index_endscan(toastscan);
systable_endscan_ordered(toastscan);
index_close(toastidx, RowExclusiveLock);
heap_close(toastrel, RowExclusiveLock);
}
@ -1332,7 +1335,7 @@ toast_fetch_datum(struct varlena * attr)
Relation toastrel;
Relation toastidx;
ScanKeyData toastkey;
IndexScanDesc toastscan;
SysScanDesc toastscan;
HeapTuple ttup;
TupleDesc toasttupDesc;
struct varlena *result;
@ -1383,9 +1386,9 @@ toast_fetch_datum(struct varlena * attr)
*/
nextidx = 0;
toastscan = index_beginscan(toastrel, toastidx,
SnapshotToast, 1, &toastkey);
while ((ttup = index_getnext(toastscan, ForwardScanDirection)) != NULL)
toastscan = systable_beginscan_ordered(toastrel, toastidx,
SnapshotToast, 1, &toastkey);
while ((ttup = systable_getnext_ordered(toastscan, ForwardScanDirection)) != NULL)
{
/*
* Have a chunk, extract the sequence number and the data
@ -1464,7 +1467,7 @@ toast_fetch_datum(struct varlena * attr)
/*
* End scan and close relations
*/
index_endscan(toastscan);
systable_endscan_ordered(toastscan);
index_close(toastidx, AccessShareLock);
heap_close(toastrel, AccessShareLock);
@ -1485,7 +1488,7 @@ toast_fetch_datum_slice(struct varlena * attr, int32 sliceoffset, int32 length)
Relation toastidx;
ScanKeyData toastkey[3];
int nscankeys;
IndexScanDesc toastscan;
SysScanDesc toastscan;
HeapTuple ttup;
TupleDesc toasttupDesc;
struct varlena *result;
@ -1592,9 +1595,9 @@ toast_fetch_datum_slice(struct varlena * attr, int32 sliceoffset, int32 length)
* The index is on (valueid, chunkidx) so they will come in order
*/
nextidx = startchunk;
toastscan = index_beginscan(toastrel, toastidx,
SnapshotToast, nscankeys, toastkey);
while ((ttup = index_getnext(toastscan, ForwardScanDirection)) != NULL)
toastscan = systable_beginscan_ordered(toastrel, toastidx,
SnapshotToast, nscankeys, toastkey);
while ((ttup = systable_getnext_ordered(toastscan, ForwardScanDirection)) != NULL)
{
/*
* Have a chunk, extract the sequence number and the data
@ -1681,7 +1684,7 @@ toast_fetch_datum_slice(struct varlena * attr, int32 sliceoffset, int32 length)
/*
* End scan and close relations
*/
index_endscan(toastscan);
systable_endscan_ordered(toastscan);
index_close(toastidx, AccessShareLock);
heap_close(toastrel, AccessShareLock);

View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/access/index/genam.c,v 1.66 2008/04/10 22:25:25 tgl Exp $
* $PostgreSQL: pgsql/src/backend/access/index/genam.c,v 1.67 2008/04/12 23:14:21 tgl Exp $
*
* NOTES
* many of the old access method routines have been turned into
@ -258,3 +258,87 @@ systable_endscan(SysScanDesc sysscan)
pfree(sysscan);
}
/*
* systable_beginscan_ordered --- set up for ordered catalog scan
*
* These routines have essentially the same API as systable_beginscan etc,
* except that they guarantee to return multiple matching tuples in
* index order. Also, for largely historical reasons, the index to use
* is opened and locked by the caller, not here.
*
* Currently we do not support non-index-based scans here. (In principle
* we could do a heapscan and sort, but the uses are in places that
* probably don't need to still work with corrupted catalog indexes.)
* For the moment, therefore, these functions are merely the thinnest of
* wrappers around index_beginscan/index_getnext. The main reason for their
* existence is to centralize possible future support of lossy operators
* in catalog scans.
*/
SysScanDesc
systable_beginscan_ordered(Relation heapRelation,
Relation indexRelation,
Snapshot snapshot,
int nkeys, ScanKey key)
{
SysScanDesc sysscan;
int i;
/* REINDEX can probably be a hard error here ... */
if (ReindexIsProcessingIndex(RelationGetRelid(indexRelation)))
elog(ERROR, "cannot do ordered scan on index \"%s\", because it is the current REINDEX target",
RelationGetRelationName(indexRelation));
/* ... but we only throw a warning about violating IgnoreSystemIndexes */
if (IgnoreSystemIndexes)
elog(WARNING, "using index \"%s\" despite IgnoreSystemIndexes",
RelationGetRelationName(indexRelation));
sysscan = (SysScanDesc) palloc(sizeof(SysScanDescData));
sysscan->heap_rel = heapRelation;
sysscan->irel = indexRelation;
/*
* Change attribute numbers to be index column numbers.
*
* This code could be generalized to search for the index key numbers
* to substitute, but for now there's no need.
*/
for (i = 0; i < nkeys; i++)
{
Assert(key[i].sk_attno == indexRelation->rd_index->indkey.values[i]);
key[i].sk_attno = i + 1;
}
sysscan->iscan = index_beginscan(heapRelation, indexRelation,
snapshot, nkeys, key);
sysscan->scan = NULL;
return sysscan;
}
/*
* systable_getnext_ordered --- get next tuple in an ordered catalog scan
*/
HeapTuple
systable_getnext_ordered(SysScanDesc sysscan, ScanDirection direction)
{
HeapTuple htup;
Assert(sysscan->irel);
htup = index_getnext(sysscan->iscan, direction);
return htup;
}
/*
* systable_endscan_ordered --- close scan, release resources
*/
void
systable_endscan_ordered(SysScanDesc sysscan)
{
Assert(sysscan->irel);
index_endscan(sysscan->iscan);
pfree(sysscan);
}

View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/access/index/indexam.c,v 1.105 2008/04/10 22:25:25 tgl Exp $
* $PostgreSQL: pgsql/src/backend/access/index/indexam.c,v 1.106 2008/04/12 23:14:21 tgl Exp $
*
* INTERFACE ROUTINES
* index_open - open an index relation by relation OID
@ -206,12 +206,7 @@ index_insert(Relation indexRelation,
/*
* index_beginscan - start a scan of an index with amgettuple
*
* Note: heapRelation may be NULL if there is no intention of calling
* index_getnext on this scan; index_getnext_indexitem will not use the
* heapRelation link (nor the snapshot). However, the caller had better
* be holding some kind of lock on the heap relation in any case, to ensure
* no one deletes it (or the index) out from under us. Caller must also
* be holding a lock on the index.
* Caller must be holding suitable locks on the heap and the index.
*/
IndexScanDesc
index_beginscan(Relation heapRelation,
@ -634,45 +629,6 @@ index_getnext(IndexScanDesc scan, ScanDirection direction)
return NULL; /* failure exit */
}
/* ----------------
* index_getnext_indexitem - get the next index tuple from a scan
*
* Finds the next index tuple satisfying the scan keys. Note that the
* corresponding heap tuple is not accessed, and thus no time qual (snapshot)
* check is done, other than the index AM's internal check for killed tuples
* (which most callers of this routine will probably want to suppress by
* setting scan->ignore_killed_tuples = false).
*
* On success (TRUE return), the heap TID of the found index entry is in
* scan->xs_ctup.t_self. scan->xs_cbuf is untouched.
* ----------------
*/
bool
index_getnext_indexitem(IndexScanDesc scan,
ScanDirection direction)
{
FmgrInfo *procedure;
bool found;
SCAN_CHECKS;
GET_SCAN_PROCEDURE(amgettuple);
/* just make sure this is false... */
scan->kill_prior_tuple = false;
/*
* have the am's gettuple proc do all the work.
*/
found = DatumGetBool(FunctionCall2(procedure,
PointerGetDatum(scan),
Int32GetDatum(direction)));
if (found)
pgstat_count_index_tuples(scan->indexRelation, 1);
return found;
}
/* ----------------
* index_getbitmap - get all tuples at once from an index scan
*

View File

@ -10,7 +10,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/catalog/catalog.c,v 1.74 2008/03/26 16:20:46 alvherre Exp $
* $PostgreSQL: pgsql/src/backend/catalog/catalog.c,v 1.75 2008/04/12 23:14:21 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -312,9 +312,7 @@ IsSharedRelation(Oid relationId)
Oid
GetNewOid(Relation relation)
{
Oid newOid;
Oid oidIndex;
Relation indexrel;
/* If relation doesn't have OIDs at all, caller is confused */
Assert(relation->rd_rel->relhasoids);
@ -342,11 +340,7 @@ GetNewOid(Relation relation)
}
/* Otherwise, use the index to find a nonconflicting OID */
indexrel = index_open(oidIndex, AccessShareLock);
newOid = GetNewOidWithIndex(relation, indexrel);
index_close(indexrel, AccessShareLock);
return newOid;
return GetNewOidWithIndex(relation, oidIndex, ObjectIdAttributeNumber);
}
/*
@ -357,16 +351,17 @@ GetNewOid(Relation relation)
* an index that will not be recognized by RelationGetOidIndex: TOAST tables
* and pg_largeobject have indexes that are usable, but have multiple columns
* and are on ordinary columns rather than a true OID column. This code
* will work anyway, so long as the OID is the index's first column.
* will work anyway, so long as the OID is the index's first column. The
* caller must pass in the actual heap attnum of the OID column, however.
*
* Caller must have a suitable lock on the relation.
*/
Oid
GetNewOidWithIndex(Relation relation, Relation indexrel)
GetNewOidWithIndex(Relation relation, Oid indexId, AttrNumber oidcolumn)
{
Oid newOid;
SnapshotData SnapshotDirty;
IndexScanDesc scan;
SysScanDesc scan;
ScanKeyData key;
bool collides;
@ -380,17 +375,17 @@ GetNewOidWithIndex(Relation relation, Relation indexrel)
newOid = GetNewObjectId();
ScanKeyInit(&key,
(AttrNumber) 1,
oidcolumn,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(newOid));
/* see notes above about using SnapshotDirty */
scan = index_beginscan(relation, indexrel,
&SnapshotDirty, 1, &key);
scan = systable_beginscan(relation, indexId, true,
&SnapshotDirty, 1, &key);
collides = HeapTupleIsValid(index_getnext(scan, ForwardScanDirection));
collides = HeapTupleIsValid(systable_getnext(scan));
index_endscan(scan);
systable_endscan(scan);
} while (collides);
return newOid;

View File

@ -24,7 +24,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/storage/large_object/inv_api.c,v 1.131 2008/03/26 21:10:38 alvherre Exp $
* $PostgreSQL: pgsql/src/backend/storage/large_object/inv_api.c,v 1.132 2008/04/12 23:14:21 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -201,7 +201,8 @@ inv_create(Oid lobjId)
{
open_lo_relation();
lobjId = GetNewOidWithIndex(lo_heap_r, lo_index_r);
lobjId = GetNewOidWithIndex(lo_heap_r, LargeObjectLOidPNIndexId,
Anum_pg_largeobject_loid);
}
/*
@ -311,7 +312,7 @@ inv_getsize(LargeObjectDesc *obj_desc)
bool found = false;
uint32 lastbyte = 0;
ScanKeyData skey[1];
IndexScanDesc sd;
SysScanDesc sd;
HeapTuple tuple;
Assert(PointerIsValid(obj_desc));
@ -323,8 +324,8 @@ inv_getsize(LargeObjectDesc *obj_desc)
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(obj_desc->id));
sd = index_beginscan(lo_heap_r, lo_index_r,
obj_desc->snapshot, 1, skey);
sd = systable_beginscan_ordered(lo_heap_r, lo_index_r,
obj_desc->snapshot, 1, skey);
/*
* Because the pg_largeobject index is on both loid and pageno, but we
@ -332,7 +333,7 @@ inv_getsize(LargeObjectDesc *obj_desc)
* large object in reverse pageno order. So, it's sufficient to examine
* the first valid tuple (== last valid page).
*/
while ((tuple = index_getnext(sd, BackwardScanDirection)) != NULL)
while ((tuple = systable_getnext_ordered(sd, BackwardScanDirection)) != NULL)
{
Form_pg_largeobject data;
bytea *datafield;
@ -356,7 +357,7 @@ inv_getsize(LargeObjectDesc *obj_desc)
break;
}
index_endscan(sd);
systable_endscan_ordered(sd);
if (!found)
ereport(ERROR,
@ -415,7 +416,7 @@ inv_read(LargeObjectDesc *obj_desc, char *buf, int nbytes)
int32 pageno = (int32) (obj_desc->offset / LOBLKSIZE);
uint32 pageoff;
ScanKeyData skey[2];
IndexScanDesc sd;
SysScanDesc sd;
HeapTuple tuple;
Assert(PointerIsValid(obj_desc));
@ -436,10 +437,10 @@ inv_read(LargeObjectDesc *obj_desc, char *buf, int nbytes)
BTGreaterEqualStrategyNumber, F_INT4GE,
Int32GetDatum(pageno));
sd = index_beginscan(lo_heap_r, lo_index_r,
obj_desc->snapshot, 2, skey);
sd = systable_beginscan_ordered(lo_heap_r, lo_index_r,
obj_desc->snapshot, 2, skey);
while ((tuple = index_getnext(sd, ForwardScanDirection)) != NULL)
while ((tuple = systable_getnext_ordered(sd, ForwardScanDirection)) != NULL)
{
Form_pg_largeobject data;
bytea *datafield;
@ -450,7 +451,7 @@ inv_read(LargeObjectDesc *obj_desc, char *buf, int nbytes)
data = (Form_pg_largeobject) GETSTRUCT(tuple);
/*
* We assume the indexscan will deliver pages in order. However,
* We expect the indexscan will deliver pages in order. However,
* there may be missing pages if the LO contains unwritten "holes". We
* want missing sections to read out as zeroes.
*/
@ -495,7 +496,7 @@ inv_read(LargeObjectDesc *obj_desc, char *buf, int nbytes)
break;
}
index_endscan(sd);
systable_endscan_ordered(sd);
return nread;
}
@ -509,7 +510,7 @@ inv_write(LargeObjectDesc *obj_desc, const char *buf, int nbytes)
int len;
int32 pageno = (int32) (obj_desc->offset / LOBLKSIZE);
ScanKeyData skey[2];
IndexScanDesc sd;
SysScanDesc sd;
HeapTuple oldtuple;
Form_pg_largeobject olddata;
bool neednextpage;
@ -555,8 +556,8 @@ inv_write(LargeObjectDesc *obj_desc, const char *buf, int nbytes)
BTGreaterEqualStrategyNumber, F_INT4GE,
Int32GetDatum(pageno));
sd = index_beginscan(lo_heap_r, lo_index_r,
obj_desc->snapshot, 2, skey);
sd = systable_beginscan_ordered(lo_heap_r, lo_index_r,
obj_desc->snapshot, 2, skey);
oldtuple = NULL;
olddata = NULL;
@ -565,12 +566,12 @@ inv_write(LargeObjectDesc *obj_desc, const char *buf, int nbytes)
while (nwritten < nbytes)
{
/*
* If possible, get next pre-existing page of the LO. We assume the
* If possible, get next pre-existing page of the LO. We expect the
* indexscan will deliver these in order --- but there may be holes.
*/
if (neednextpage)
{
if ((oldtuple = index_getnext(sd, ForwardScanDirection)) != NULL)
if ((oldtuple = systable_getnext_ordered(sd, ForwardScanDirection)) != NULL)
{
if (HeapTupleHasNulls(oldtuple)) /* paranoia */
elog(ERROR, "null field found in pg_largeobject");
@ -685,7 +686,7 @@ inv_write(LargeObjectDesc *obj_desc, const char *buf, int nbytes)
pageno++;
}
index_endscan(sd);
systable_endscan_ordered(sd);
CatalogCloseIndexes(indstate);
@ -704,7 +705,7 @@ inv_truncate(LargeObjectDesc *obj_desc, int len)
int32 pageno = (int32) (len / LOBLKSIZE);
int off;
ScanKeyData skey[2];
IndexScanDesc sd;
SysScanDesc sd;
HeapTuple oldtuple;
Form_pg_largeobject olddata;
struct
@ -743,15 +744,15 @@ inv_truncate(LargeObjectDesc *obj_desc, int len)
BTGreaterEqualStrategyNumber, F_INT4GE,
Int32GetDatum(pageno));
sd = index_beginscan(lo_heap_r, lo_index_r,
obj_desc->snapshot, 2, skey);
sd = systable_beginscan_ordered(lo_heap_r, lo_index_r,
obj_desc->snapshot, 2, skey);
/*
* If possible, get the page the truncation point is in. The truncation
* point may be beyond the end of the LO or in a hole.
*/
olddata = NULL;
if ((oldtuple = index_getnext(sd, ForwardScanDirection)) != NULL)
if ((oldtuple = systable_getnext_ordered(sd, ForwardScanDirection)) != NULL)
{
if (HeapTupleHasNulls(oldtuple)) /* paranoia */
elog(ERROR, "null field found in pg_largeobject");
@ -846,12 +847,12 @@ inv_truncate(LargeObjectDesc *obj_desc, int len)
/*
* Delete any pages after the truncation point
*/
while ((oldtuple = index_getnext(sd, ForwardScanDirection)) != NULL)
while ((oldtuple = systable_getnext_ordered(sd, ForwardScanDirection)) != NULL)
{
simple_heap_delete(lo_heap_r, &oldtuple->t_self);
}
index_endscan(sd);
systable_endscan_ordered(sd);
CatalogCloseIndexes(indstate);

View File

@ -20,7 +20,7 @@
* Copyright (c) 2006-2008, PostgreSQL Global Development Group
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/utils/cache/ts_cache.c,v 1.6 2008/03/26 21:10:39 alvherre Exp $
* $PostgreSQL: pgsql/src/backend/utils/cache/ts_cache.c,v 1.7 2008/04/12 23:14:21 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -419,7 +419,7 @@ lookup_ts_config_cache(Oid cfgId)
Relation maprel;
Relation mapidx;
ScanKeyData mapskey;
IndexScanDesc mapscan;
SysScanDesc mapscan;
HeapTuple maptup;
ListDictionary maplists[MAXTOKENTYPE + 1];
Oid mapdicts[MAXDICTSPERTT];
@ -488,9 +488,10 @@ lookup_ts_config_cache(Oid cfgId)
maprel = heap_open(TSConfigMapRelationId, AccessShareLock);
mapidx = index_open(TSConfigMapIndexId, AccessShareLock);
mapscan = index_beginscan(maprel, mapidx, SnapshotNow, 1, &mapskey);
mapscan = systable_beginscan_ordered(maprel, mapidx,
SnapshotNow, 1, &mapskey);
while ((maptup = index_getnext(mapscan, ForwardScanDirection)) != NULL)
while ((maptup = systable_getnext_ordered(mapscan, ForwardScanDirection)) != NULL)
{
Form_pg_ts_config_map cfgmap = (Form_pg_ts_config_map) GETSTRUCT(maptup);
int toktype = cfgmap->maptokentype;
@ -524,7 +525,7 @@ lookup_ts_config_cache(Oid cfgId)
}
}
index_endscan(mapscan);
systable_endscan_ordered(mapscan);
index_close(mapidx, AccessShareLock);
heap_close(maprel, AccessShareLock);

View File

@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/access/genam.h,v 1.70 2008/04/10 22:25:25 tgl Exp $
* $PostgreSQL: pgsql/src/include/access/genam.h,v 1.71 2008/04/12 23:14:21 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -108,8 +108,6 @@ extern void index_endscan(IndexScanDesc scan);
extern void index_markpos(IndexScanDesc scan);
extern void index_restrpos(IndexScanDesc scan);
extern HeapTuple index_getnext(IndexScanDesc scan, ScanDirection direction);
extern bool index_getnext_indexitem(IndexScanDesc scan,
ScanDirection direction);
extern int64 index_getbitmap(IndexScanDesc scan, TIDBitmap *bitmap);
extern IndexBulkDeleteResult *index_bulk_delete(IndexVacuumInfo *info,
@ -140,5 +138,12 @@ extern SysScanDesc systable_beginscan(Relation heapRelation,
int nkeys, ScanKey key);
extern HeapTuple systable_getnext(SysScanDesc sysscan);
extern void systable_endscan(SysScanDesc sysscan);
extern SysScanDesc systable_beginscan_ordered(Relation heapRelation,
Relation indexRelation,
Snapshot snapshot,
int nkeys, ScanKey key);
extern HeapTuple systable_getnext_ordered(SysScanDesc sysscan,
ScanDirection direction);
extern void systable_endscan_ordered(SysScanDesc sysscan);
#endif /* GENAM_H */

View File

@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/access/relscan.h,v 1.62 2008/04/10 22:25:25 tgl Exp $
* $PostgreSQL: pgsql/src/include/access/relscan.h,v 1.63 2008/04/12 23:14:21 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -76,14 +76,12 @@ typedef struct IndexScanDescData
/* index access method's private state */
void *opaque; /* access-method-specific info */
/*
* xs_ctup/xs_cbuf are valid after a successful index_getnext. After
* index_getnext_indexitem, xs_ctup.t_self contains the heap tuple TID
* from the index entry, but its other fields are not valid.
*/
/* xs_ctup/xs_cbuf are valid after a successful index_getnext */
HeapTupleData xs_ctup; /* current heap tuple, if any */
Buffer xs_cbuf; /* current heap buffer in scan, if any */
/* NB: if xs_cbuf is not InvalidBuffer, we hold a pin on that buffer */
/* state data for traversing HOT chains in index_getnext */
TransactionId xs_prev_xmax; /* previous HOT chain member's XMAX, if any */
OffsetNumber xs_next_hot; /* next member of HOT chain, if any */
bool xs_hot_dead; /* T if all members of HOT chain are dead */

View File

@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/catalog/catalog.h,v 1.38 2008/01/01 19:45:56 momjian Exp $
* $PostgreSQL: pgsql/src/include/catalog/catalog.h,v 1.39 2008/04/12 23:14:21 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -34,7 +34,8 @@ extern bool IsReservedName(const char *name);
extern bool IsSharedRelation(Oid relationId);
extern Oid GetNewOid(Relation relation);
extern Oid GetNewOidWithIndex(Relation relation, Relation indexrel);
extern Oid GetNewOidWithIndex(Relation relation, Oid indexId,
AttrNumber oidcolumn);
extern Oid GetNewRelFileNode(Oid reltablespace, bool relisshared,
Relation pg_class);