* that we can access it randomly. When the caller does not need random
* access, we return from tuplesort_performsort() as soon as we are down
* to one run per logical tape. The final merge is then performed
- * on-the-fly as the caller repeatedly calls tuplesort_gettuple; this
+ * on-the-fly as the caller repeatedly calls tuplesort_getXXX; this
* saves one cycle of writing all the data out to disk and reading it in.
*
* Before Postgres 8.2, we always used a seven-tape polyphase merge, on the
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/utils/sort/tuplesort.c,v 1.66 2006/05/23 21:37:59 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/utils/sort/tuplesort.c,v 1.67 2006/06/27 16:53:02 tgl Exp $
*
*-------------------------------------------------------------------------
*/
/*
* The objects we actually sort are SortTuple structs. These contain
- * a pointer to the tuple proper (might be a HeapTuple or IndexTuple),
+ * a pointer to the tuple proper (might be a MinimalTuple or IndexTuple),
* which is a separate palloc chunk --- we assume it is just one chunk and
* can be freed by a simple pfree(). SortTuples also contain the tuple's
* first key column in Datum/nullflag format, and an index integer.
bool markpos_eof; /* saved "eof_reached" */
/*
- * These variables are specific to the HeapTuple case; they are set by
- * tuplesort_begin_heap and used only by the HeapTuple routines.
+ * These variables are specific to the MinimalTuple case; they are set by
+ * tuplesort_begin_heap and used only by the MinimalTuple routines.
*/
TupleDesc tupDesc;
ScanKey scanKeys; /* array of length nKeys */
*
* Initialize for a tuple sort operation.
*
- * After calling tuplesort_begin, the caller should call tuplesort_puttuple
+ * After calling tuplesort_begin, the caller should call tuplesort_putXXX
* zero or more times, then call tuplesort_performsort when all the tuples
* have been supplied. After performsort, retrieve the tuples in sorted
- * order by calling tuplesort_gettuple until it returns NULL. (If random
+ * order by calling tuplesort_getXXX until it returns false/NULL. (If random
* access was requested, rescan, markpos, and restorepos can also be called.)
- * For Datum sorts, putdatum/getdatum are used instead of puttuple/gettuple.
* Call tuplesort_end to terminate the operation and release memory/disk space.
*
* Each variant of tuplesort_begin has a workMem parameter specifying the
*
* Release resources and clean up.
*
- * NOTE: after calling this, any tuple pointers returned by tuplesort_gettuple
- * or datum pointers returned by tuplesort_getdatum are pointing to garbage.
- * Be careful not to attempt to use or free such pointers afterwards!
+ * NOTE: after calling this, any pointers returned by tuplesort_getXXX are
+ * pointing to garbage. Be careful not to attempt to use or free such
+ * pointers afterwards!
*/
void
tuplesort_end(Tuplesortstate *state)
/*
* Accept one tuple while collecting input data for sort.
*
+ * Note that the input data is always copied; the caller need not save it.
+ */
+void
+tuplesort_puttupleslot(Tuplesortstate *state, TupleTableSlot *slot)
+{
+ MemoryContext oldcontext = MemoryContextSwitchTo(state->sortcontext);
+ SortTuple stup;
+
+ /*
+ * Copy the given tuple into memory we control, and decrease availMem.
+ * Then call the common code.
+ */
+ COPYTUP(state, &stup, (void *) slot);
+
+ puttuple_common(state, &stup);
+
+ MemoryContextSwitchTo(oldcontext);
+}
+
+/*
+ * Accept one index tuple while collecting input data for sort.
+ *
* Note that the input tuple is always copied; the caller need not save it.
*/
void
-tuplesort_puttuple(Tuplesortstate *state, void *tuple)
+tuplesort_putindextuple(Tuplesortstate *state, IndexTuple tuple)
{
MemoryContext oldcontext = MemoryContextSwitchTo(state->sortcontext);
SortTuple stup;
/*
* Copy the given tuple into memory we control, and decrease availMem.
- * Then call the code shared with the Datum case.
+ * Then call the common code.
*/
- COPYTUP(state, &stup, tuple);
+ COPYTUP(state, &stup, (void *) tuple);
puttuple_common(state, &stup);
/*
* If it's a pass-by-reference value, copy it into memory we control,
- * and decrease availMem. Then call the code shared with the tuple case.
+ * and decrease availMem. Then call the common code.
*/
if (isNull || state->datumTypeByVal)
{
/*
* Fetch the next tuple in either forward or back direction.
+ * If successful, put tuple in slot and return TRUE; else, clear the slot
+ * and return FALSE.
+ */
+bool
+tuplesort_gettupleslot(Tuplesortstate *state, bool forward,
+ TupleTableSlot *slot)
+{
+ MemoryContext oldcontext = MemoryContextSwitchTo(state->sortcontext);
+ SortTuple stup;
+ bool should_free;
+
+ if (!tuplesort_gettuple_common(state, forward, &stup, &should_free))
+ stup.tuple = NULL;
+
+ MemoryContextSwitchTo(oldcontext);
+
+ if (stup.tuple)
+ {
+ ExecStoreMinimalTuple((MinimalTuple) stup.tuple, slot, should_free);
+ return true;
+ }
+ else
+ {
+ ExecClearTuple(slot);
+ return false;
+ }
+}
+
+/*
+ * Fetch the next index tuple in either forward or back direction.
* Returns NULL if no more tuples. If *should_free is set, the
* caller must pfree the returned tuple when done with it.
*/
-void *
-tuplesort_gettuple(Tuplesortstate *state, bool forward,
- bool *should_free)
+IndexTuple
+tuplesort_getindextuple(Tuplesortstate *state, bool forward,
+ bool *should_free)
{
MemoryContext oldcontext = MemoryContextSwitchTo(state->sortcontext);
SortTuple stup;
MemoryContextSwitchTo(oldcontext);
- return stup.tuple;
+ return (IndexTuple) stup.tuple;
}
/*
/*
- * Routines specialized for HeapTuple case
+ * Routines specialized for HeapTuple (actually MinimalTuple) case
*/
static int
comparetup_heap(Tuplesortstate *state, const SortTuple *a, const SortTuple *b)
{
ScanKey scanKey = state->scanKeys;
- HeapTuple ltup;
- HeapTuple rtup;
+ HeapTupleData ltup;
+ HeapTupleData rtup;
TupleDesc tupDesc;
int nkey;
int32 compare;
return compare;
/* Compare additional sort keys */
- ltup = (HeapTuple) a->tuple;
- rtup = (HeapTuple) b->tuple;
+ ltup.t_len = ((MinimalTuple) a->tuple)->t_len + MINIMAL_TUPLE_OFFSET;
+ ltup.t_data = (HeapTupleHeader) ((char *) a->tuple - MINIMAL_TUPLE_OFFSET);
+ rtup.t_len = ((MinimalTuple) b->tuple)->t_len + MINIMAL_TUPLE_OFFSET;
+ rtup.t_data = (HeapTupleHeader) ((char *) b->tuple - MINIMAL_TUPLE_OFFSET);
tupDesc = state->tupDesc;
scanKey++;
for (nkey = 1; nkey < state->nKeys; nkey++, scanKey++)
bool isnull1,
isnull2;
- datum1 = heap_getattr(ltup, attno, tupDesc, &isnull1);
- datum2 = heap_getattr(rtup, attno, tupDesc, &isnull2);
+ datum1 = heap_getattr(<up, attno, tupDesc, &isnull1);
+ datum2 = heap_getattr(&rtup, attno, tupDesc, &isnull2);
compare = inlineApplySortFunction(&scanKey->sk_func,
state->sortFnKinds[nkey],
static void
copytup_heap(Tuplesortstate *state, SortTuple *stup, void *tup)
{
- HeapTuple tuple = (HeapTuple) tup;
+ /*
+ * We expect the passed "tup" to be a TupleTableSlot, and form a
+ * MinimalTuple using the exported interface for that.
+ */
+ TupleTableSlot *slot = (TupleTableSlot *) tup;
+ MinimalTuple tuple;
+ HeapTupleData htup;
/* copy the tuple into sort storage */
- stup->tuple = (void *) heap_copytuple(tuple);
- USEMEM(state, GetMemoryChunkSpace(stup->tuple));
+ tuple = ExecCopySlotMinimalTuple(slot);
+ stup->tuple = (void *) tuple;
+ USEMEM(state, GetMemoryChunkSpace(tuple));
/* set up first-column key value */
- stup->datum1 = heap_getattr((HeapTuple) stup->tuple,
+ htup.t_len = tuple->t_len + MINIMAL_TUPLE_OFFSET;
+ htup.t_data = (HeapTupleHeader) ((char *) tuple - MINIMAL_TUPLE_OFFSET);
+ stup->datum1 = heap_getattr(&htup,
state->scanKeys[0].sk_attno,
state->tupDesc,
&stup->isnull1);
}
/*
- * When writing HeapTuples to tape, we strip off all tuple identity and
- * transaction visibility information, because those fields aren't really
- * interesting for in-memory tuples (they may or may not be valid in the
- * incoming tuples, depending on the plan that's feeding the sort). We
- * only need to store t_natts, t_infomask, the nulls bitmap if any, and
- * the user data.
- *
- * You might think that we could omit storing t_natts, but you'd be wrong:
- * the incoming tuple might be a physical disk tuple with fewer columns
- * than the table's current logical tupdesc.
+ * Since MinimalTuple already has length in its first word, we don't need
+ * to write that separately.
*/
-typedef struct TapeTupleHeader
-{
- unsigned int tuplen; /* required header of a tape item */
- int16 natts; /* number of attributes */
- uint16 infomask; /* various flag bits */
- /* nulls bitmap follows if HEAP_HASNULL, then actual tuple data */
-} TapeTupleHeader;
-
static void
writetup_heap(Tuplesortstate *state, int tapenum, SortTuple *stup)
{
- HeapTuple tuple = (HeapTuple) stup->tuple;
- HeapTupleHeader t_data = tuple->t_data;
- TapeTupleHeader tapehdr;
- unsigned int datalen;
- unsigned int nullslen;
-
- Assert(tuple->t_len >= t_data->t_hoff);
- datalen = tuple->t_len - t_data->t_hoff;
- if (HeapTupleHasNulls(tuple))
- nullslen = BITMAPLEN(t_data->t_natts);
- else
- nullslen = 0;
- tapehdr.tuplen = sizeof(TapeTupleHeader) + nullslen + datalen;
- tapehdr.natts = t_data->t_natts;
- tapehdr.infomask = t_data->t_infomask;
- LogicalTapeWrite(state->tapeset, tapenum,
- (void *) &tapehdr, sizeof(tapehdr));
- if (nullslen)
- LogicalTapeWrite(state->tapeset, tapenum,
- (void *) t_data->t_bits, nullslen);
+ MinimalTuple tuple = (MinimalTuple) stup->tuple;
+ unsigned int tuplen = tuple->t_len;
+
LogicalTapeWrite(state->tapeset, tapenum,
- (char *) t_data + t_data->t_hoff, datalen);
+ (void *) tuple, tuplen);
if (state->randomAccess) /* need trailing length word? */
LogicalTapeWrite(state->tapeset, tapenum,
- (void *) &tapehdr.tuplen, sizeof(tapehdr.tuplen));
+ (void *) &tuplen, sizeof(tuplen));
FREEMEM(state, GetMemoryChunkSpace(tuple));
- heap_freetuple(tuple);
+ heap_free_minimal_tuple(tuple);
}
static void
readtup_heap(Tuplesortstate *state, SortTuple *stup,
int tapenum, unsigned int len)
{
- TapeTupleHeader tapehdr;
- unsigned int datalen;
- unsigned int nullslen;
- unsigned int hoff;
- HeapTuple tuple;
- HeapTupleHeader t_data;
+ MinimalTuple tuple = (MinimalTuple) palloc(len);
+ unsigned int tuplen;
+ HeapTupleData htup;
- /* read in the rest of the header */
- if (LogicalTapeRead(state->tapeset, tapenum,
- (char *) &tapehdr + sizeof(unsigned int),
- sizeof(tapehdr) - sizeof(unsigned int)) !=
- sizeof(tapehdr) - sizeof(unsigned int))
- elog(ERROR, "unexpected end of data");
- /* reconstruct lengths of null bitmap and data part */
- if (tapehdr.infomask & HEAP_HASNULL)
- nullslen = BITMAPLEN(tapehdr.natts);
- else
- nullslen = 0;
- datalen = len - sizeof(TapeTupleHeader) - nullslen;
- /* determine overhead size of tuple (should match heap_form_tuple) */
- hoff = offsetof(HeapTupleHeaderData, t_bits) + nullslen;
- if (tapehdr.infomask & HEAP_HASOID)
- hoff += sizeof(Oid);
- hoff = MAXALIGN(hoff);
- /* Allocate the space in one chunk, like heap_form_tuple */
- tuple = (HeapTuple) palloc(HEAPTUPLESIZE + hoff + datalen);
USEMEM(state, GetMemoryChunkSpace(tuple));
- t_data = (HeapTupleHeader) ((char *) tuple + HEAPTUPLESIZE);
- /* make sure unused header fields are zeroed */
- MemSetAligned(t_data, 0, hoff);
- /* reconstruct the HeapTupleData fields */
- tuple->t_len = hoff + datalen;
- ItemPointerSetInvalid(&(tuple->t_self));
- tuple->t_tableOid = InvalidOid;
- tuple->t_data = t_data;
- /* reconstruct the HeapTupleHeaderData fields */
- ItemPointerSetInvalid(&(t_data->t_ctid));
- t_data->t_natts = tapehdr.natts;
- t_data->t_infomask = (tapehdr.infomask & ~HEAP_XACT_MASK)
- | (HEAP_XMIN_INVALID | HEAP_XMAX_INVALID);
- t_data->t_hoff = hoff;
- /* read in the null bitmap if any */
- if (nullslen)
- if (LogicalTapeRead(state->tapeset, tapenum,
- (void *) t_data->t_bits, nullslen) != nullslen)
- elog(ERROR, "unexpected end of data");
- /* and the data proper */
+ /* read in the tuple proper */
+ tuple->t_len = len;
if (LogicalTapeRead(state->tapeset, tapenum,
- (char *) t_data + hoff, datalen) != datalen)
+ (void *) ((char *) tuple + sizeof(int)),
+ len - sizeof(int)) != (size_t) (len - sizeof(int)))
elog(ERROR, "unexpected end of data");
if (state->randomAccess) /* need trailing length word? */
- if (LogicalTapeRead(state->tapeset, tapenum, (void *) &tapehdr.tuplen,
- sizeof(tapehdr.tuplen)) != sizeof(tapehdr.tuplen))
+ if (LogicalTapeRead(state->tapeset, tapenum, (void *) &tuplen,
+ sizeof(tuplen)) != sizeof(tuplen))
elog(ERROR, "unexpected end of data");
stup->tuple = (void *) tuple;
/* set up first-column key value */
- stup->datum1 = heap_getattr(tuple,
+ htup.t_len = tuple->t_len + MINIMAL_TUPLE_OFFSET;
+ htup.t_data = (HeapTupleHeader) ((char *) tuple - MINIMAL_TUPLE_OFFSET);
+ stup->datum1 = heap_getattr(&htup,
state->scanKeys[0].sk_attno,
state->tupDesc,
&stup->isnull1);
* Portions Copyright (c) 1996-2006, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/include/utils/tuplesort.h,v 1.20 2006/05/23 21:37:59 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/utils/tuplesort.h,v 1.21 2006/06/27 16:53:02 tgl Exp $
*
*-------------------------------------------------------------------------
*/
#ifndef TUPLESORT_H
#define TUPLESORT_H
-#include "access/htup.h"
#include "access/itup.h"
+#include "executor/tuptable.h"
#include "fmgr.h"
-/* Tuplesortstate is an opaque type whose details are not known outside tuplesort.c. */
+/* Tuplesortstate is an opaque type whose details are not known outside
+ * tuplesort.c.
+ */
typedef struct Tuplesortstate Tuplesortstate;
/*
* We provide two different interfaces to what is essentially the same
* code: one for sorting HeapTuples and one for sorting IndexTuples.
* They differ primarily in the way that the sort key information is
- * supplied. Also, tuplesort.c guarantees to preserve all the header
- * fields of an IndexTuple, but when sorting HeapTuples only the user data
- * is guaranteed preserved, not the "system columns" (tuple identity and
- * transaction visibility info).
+ * supplied. Also, the HeapTuple case actually stores MinimalTuples,
+ * which means it doesn't preserve the "system columns" (tuple identity and
+ * transaction visibility info). The IndexTuple case does preserve all
+ * the header fields of an index entry. In the HeapTuple case we can
+ * save some cycles by passing and returning the tuples in TupleTableSlots,
+ * rather than forming actual HeapTuples (which'd have to be converted to
+ * MinimalTuples).
*
* Yet a third slightly different interface supports sorting bare Datums.
*/
Oid sortOperator,
int workMem, bool randomAccess);
-extern void tuplesort_puttuple(Tuplesortstate *state, void *tuple);
-
+extern void tuplesort_puttupleslot(Tuplesortstate *state,
+ TupleTableSlot *slot);
+extern void tuplesort_putindextuple(Tuplesortstate *state, IndexTuple tuple);
extern void tuplesort_putdatum(Tuplesortstate *state, Datum val,
bool isNull);
extern void tuplesort_performsort(Tuplesortstate *state);
-extern void *tuplesort_gettuple(Tuplesortstate *state, bool forward,
- bool *should_free);
-
-#define tuplesort_getheaptuple(state, forward, should_free) \
- ((HeapTuple) tuplesort_gettuple(state, forward, should_free))
-#define tuplesort_getindextuple(state, forward, should_free) \
- ((IndexTuple) tuplesort_gettuple(state, forward, should_free))
-
+extern bool tuplesort_gettupleslot(Tuplesortstate *state, bool forward,
+ TupleTableSlot *slot);
+extern IndexTuple tuplesort_getindextuple(Tuplesortstate *state, bool forward,
+ bool *should_free);
extern bool tuplesort_getdatum(Tuplesortstate *state, bool forward,
Datum *val, bool *isNull);
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