src/include/executor/tuptable.h - hawq - Git at Google

 /*-------------------------------------------------------------------------
  *
  * tuptable.h
  *	  tuple table support stuff
  *
  *
  * Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * $PostgreSQL: pgsql/src/include/executor/tuptable.h,v 1.36 2006/10/04 00:30:08 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
 #ifndef TUPTABLE_H
 #define TUPTABLE_H

 #include "access/htup.h"
 #include "access/tupdesc.h"
 #include "access/heapam.h"
 #include "access/memtup.h"
 #include "storage/buf.h"

 /*----------
  * The executor stores tuples in a "tuple table" which is composed of
  * independent TupleTableSlots.  There are several cases we need to handle:
  *		1. physical tuple in a disk buffer page
  *		2. physical tuple constructed in palloc'ed memory
  *		3. "minimal" physical tuple constructed in palloc'ed memory
  *		4. "virtual" tuple consisting of Datum/isnull arrays
  *
  * The first two cases are similar in that they both deal with "materialized"
  * tuples, but resource management is different.  For a tuple in a disk page
  * we need to hold a pin on the buffer until the TupleTableSlot's reference
  * to the tuple is dropped; while for a palloc'd tuple we usually want the
  * tuple pfree'd when the TupleTableSlot's reference is dropped.
  *
  * A "minimal" tuple is handled similarly to a palloc'd regular tuple.
  * At present, minimal tuples never are stored in buffers, so there is no
  * parallel to case 1.	Note that a minimal tuple has no "system columns".
  * (Actually, it could have an OID, but we have no need to access the OID.)
  *
  * A "virtual" tuple is an optimization used to minimize physical data
  * copying in a nest of plan nodes.  Any pass-by-reference Datums in the
  * tuple point to storage that is not directly associated with the
  * TupleTableSlot; generally they will point to part of a tuple stored in
  * a lower plan node's output TupleTableSlot, or to a function result
  * constructed in a plan node's per-tuple econtext.  It is the responsibility
  * of the generating plan node to be sure these resources are not released
  * for as long as the virtual tuple needs to be valid.	We only use virtual
  * tuples in the result slots of plan nodes --- tuples to be copied anywhere
  * else need to be "materialized" into physical tuples.  Note also that a
  * virtual tuple does not have any "system columns".
  *
  * The Datum/isnull arrays of a TupleTableSlot serve double duty.  When the
  * slot contains a virtual tuple, they are the authoritative data.	When the
  * slot contains a physical tuple, the arrays contain data extracted from
  * the tuple.  (In this state, any pass-by-reference Datums point into
  * the physical tuple.)  The extracted information is built "lazily",
  * ie, only as needed.	This serves to avoid repeated extraction of data
  * from the physical tuple.
  *
  * A TupleTableSlot can also be "empty", holding no valid data.  This is
  * the only valid state for a freshly-created slot that has not yet had a
  * tuple descriptor assigned to it.  In this state, tts_isempty must be
  * TRUE, tts_shouldFree FALSE, tts_tuple NULL, tts_buffer InvalidBuffer,
  * and tts_nvalid zero.
  *
  * The tupleDescriptor is simply referenced, not copied, by the TupleTableSlot
  * code.  The caller of ExecSetSlotDescriptor() is responsible for providing
  * a descriptor that will live as long as the slot does.  (Typically, both
  * slots and descriptors are in per-query memory and are freed by memory
  * context deallocation at query end; so it's not worth providing any extra
  * mechanism to do more.  However, the slot will increment the tupdesc
  * reference count if a reference-counted tupdesc is supplied.)
  *
  * When tts_shouldFree is true, the physical tuple is "owned" by the slot
  * and should be freed when the slot's reference to the tuple is dropped.
  *
  * If tts_buffer is not InvalidBuffer, then the slot is holding a pin
  * on the indicated buffer page; drop the pin when we release the
  * slot's reference to that buffer.  (tts_shouldFree should always be
  * false in such a case, since presumably tts_tuple is pointing at the
  * buffer page.)
  *
  * tts_nvalid indicates the number of valid columns in the tts_values/isnull
  * arrays.	When the slot is holding a "virtual" tuple this must be equal
  * to the descriptor's natts.  When the slot is holding a physical tuple
  * this is equal to the number of columns we have extracted (we always
  * extract columns from left to right, so there are no holes).
  *
  * tts_values/tts_isnull are allocated when a descriptor is assigned to the
  * slot; they are of length equal to the descriptor's natts.
  *
  * tts_mintuple must always be NULL if the slot does not hold a "minimal"
  * tuple.  When it does, tts_mintuple points to the actual MinimalTupleData
  * object (the thing to be pfree'd if tts_shouldFree is true).  In this case
  * tts_tuple points at tts_minhdr and the fields of that are set correctly
  * for access to the minimal tuple; in particular, tts_minhdr.t_data points
  * MINIMAL_TUPLE_OFFSET bytes before tts_mintuple.	(tts_mintuple is therefore
  * redundant, but for code simplicity we store it explicitly anyway.)  This
  * case otherwise behaves identically to the regular-physical-tuple case.
  *
  * tts_slow/tts_off are saved state for slot_deform_tuple, and should not
  * be touched by any other code.
  *----------
  */

 /* tts_flags */
 #define         TTS_ISEMPTY     1
 #define         TTS_SHOULDFREE 	2
 #define         TTS_VIRTUAL     4

 typedef struct TupleTableSlot
 {
 	NodeTag		type;		/* vestigial ... allows IsA tests */
 	int         PRIVATE_tts_flags;      /* TTS_xxx flags */

 	/* Heap tuple stuff */
 	HeapTuple PRIVATE_tts_heaptuple;
 	void    *PRIVATE_tts_htup_buf;
 	uint32   PRIVATE_tts_htup_buf_len;

 	/* Mem tuple stuff */
 	MemTuple PRIVATE_tts_memtuple;
 	void 	*PRIVATE_tts_mtup_buf;
 	uint32  PRIVATE_tts_mtup_buf_len;
 	ItemPointerData PRIVATE_tts_synthetic_ctid;	/* needed if memtuple is stored on disk */

 	/* Virtual tuple stuff */
 	int 	PRIVATE_tts_nvalid;		/* number of valid virtual tup entries */
 	long    PRIVATE_tts_off; 		/* hack to remember state of last decoding. */
 	bool    PRIVATE_tts_slow; 		/* hack to remember state of last decoding. */
 	Datum 	*PRIVATE_tts_values;		/* virtual tuple values */
 	bool 	*PRIVATE_tts_isnull;		/* virtual tuple nulls */

 	Datum 	PRIVATE_tb;             /* Vectorized Execution TupleBatch */

 	TupleDesc	tts_tupleDescriptor;	/* slot's tuple descriptor */
 	MemTupleBinding *tts_mt_bind;		/* mem tuple's binding */
 	MemoryContext 	tts_mcxt;		/* slot itself is in this context */
 	Buffer		tts_buffer;		/* tuple's buffer, or InvalidBuffer */

     /* System attributes */
     Oid         tts_tableOid;
 } TupleTableSlot;

 static inline bool TupIsNull(TupleTableSlot *slot)
 {
 	return (slot == NULL || (slot->PRIVATE_tts_flags & TTS_ISEMPTY) != 0);
 }
 static inline void TupClearIsEmpty(TupleTableSlot *slot)
 {
 	slot->PRIVATE_tts_flags &= (~TTS_ISEMPTY);
 }
 static inline bool TupShouldFree(TupleTableSlot *slot)
 {
 	Assert(slot);
 	return ((slot->PRIVATE_tts_flags & TTS_SHOULDFREE) != 0);
 }
 static inline void TupSetShouldFree(TupleTableSlot *slot)
 {
 	slot->PRIVATE_tts_flags |= TTS_SHOULDFREE;
 }
 static inline void TupClearShouldFree(TupleTableSlot *slot)
 {
 	slot->PRIVATE_tts_flags &= (~TTS_SHOULDFREE);
 }
 static inline bool TupHasHeapTuple(TupleTableSlot *slot)
 {
 	Assert(slot);
 	return slot->PRIVATE_tts_heaptuple != NULL;
 }
 static inline bool TupHasMemTuple(TupleTableSlot *slot)
 {
 	Assert(slot);
 	return slot->PRIVATE_tts_memtuple != NULL;
 }
 static inline bool TupHasVirtualTuple(TupleTableSlot *slot)
 {
 	Assert(slot);
     return (slot->PRIVATE_tts_flags & TTS_VIRTUAL) ? true : false;
 }
 static inline HeapTuple TupGetHeapTuple(TupleTableSlot *slot)
 {
 	Assert(TupHasHeapTuple(slot));
 	Assert(!is_heaptuple_memtuple(slot->PRIVATE_tts_heaptuple));
 	return slot->PRIVATE_tts_heaptuple;
 }
 static inline MemTuple TupGetMemTuple(TupleTableSlot *slot)
 {
 	Assert(TupHasMemTuple(slot));
 	return slot->PRIVATE_tts_memtuple;
 }

 static inline void free_heaptuple_memtuple(TupleTableSlot *slot)
 {
 	if(TupShouldFree(slot))
 	{
 		if(slot->PRIVATE_tts_heaptuple && slot->PRIVATE_tts_heaptuple != slot->PRIVATE_tts_htup_buf)
 			pfree(slot->PRIVATE_tts_heaptuple);

 		if(slot->PRIVATE_tts_memtuple && slot->PRIVATE_tts_memtuple != slot->PRIVATE_tts_mtup_buf)
 			pfree(slot->PRIVATE_tts_memtuple);
 	}

 	slot->PRIVATE_tts_heaptuple = NULL;
 	slot->PRIVATE_tts_memtuple = NULL;
 }

 static inline void TupSetVirtualTuple(TupleTableSlot *slot)
 {
 	Assert(slot);
 	slot->PRIVATE_tts_flags |= TTS_VIRTUAL;
 }

 static inline void TupSetVirtualTupleNValid(TupleTableSlot *slot, int nvalid)
 {
         free_heaptuple_memtuple(slot);
         slot->PRIVATE_tts_flags = TTS_VIRTUAL;
         slot->PRIVATE_tts_nvalid = nvalid;
 }

 static inline Datum *slot_get_values(TupleTableSlot *slot)
 {
 	return slot->PRIVATE_tts_values;
 }

 static inline bool *slot_get_isnull(TupleTableSlot *slot)
 {
 	return slot->PRIVATE_tts_isnull;
 }

 extern void _slot_getsomeattrs(TupleTableSlot *slot, int attnum);
 static inline void slot_getsomeattrs(TupleTableSlot *slot, int attnum)
 {

 	if(TupHasVirtualTuple(slot))
 	{
 		if(slot->PRIVATE_tts_nvalid >= attnum)
 			return;
 	}

 	if(TupHasMemTuple(slot))
 	{
 		int i;
 		for(i=0; i<attnum; ++i)
 			slot->PRIVATE_tts_values[i] = memtuple_getattr(
 					slot->PRIVATE_tts_memtuple, slot->tts_mt_bind,
 					i+1, &(slot->PRIVATE_tts_isnull[i]));

 		TupSetVirtualTuple(slot);
 		slot->PRIVATE_tts_nvalid = attnum;
 		return;
 	}

 	_slot_getsomeattrs(slot, attnum);
 	TupSetVirtualTuple(slot);
 }


 static inline void slot_getallattrs(TupleTableSlot *slot)
 {
 	slot_getsomeattrs(slot, slot->tts_tupleDescriptor->natts);
 }

 extern Datum slot_getsysattr(TupleTableSlot *slot, int attnum, bool *isnull);

 /*
  * Set the synthetic ctid to a given ctid value.
  *
  * If the slot contains a memtuple or a virtual tuple, the PRIVATE_tts_synthetic_ctid
  * is set to the given ctid value. If the slot contains a heap tuple, then t_self
  * in the heap tuple is set to the given ctid value.
  *
  * This function will set both PRIVATE_tts_synthetic_ctid and heaptuple->t_self when
  * both heap tuple and memtuple or virtual tuple are presented.
  */
 static inline void slot_set_ctid(TupleTableSlot *slot, ItemPointer new_ctid)
 {
 	Assert(slot);

 	if (TupHasHeapTuple(slot))
 	{
 		HeapTuple tuple = TupGetHeapTuple(slot);
 		tuple->t_self = *new_ctid;
 	}

 	if (TupHasMemTuple(slot) || TupHasVirtualTuple(slot))
 		slot->PRIVATE_tts_synthetic_ctid = *new_ctid;
 }

 extern void slot_set_ctid_from_fake(TupleTableSlot *slot, ItemPointerData *fake_ctid);

 /*
  * Retrieve the synthetic ctid value from the slot.
  *
  * This function assumes that the PRIVATE_tts_synthetic_ctid and heaptuple->t_self
  * are in sync if both of them are presented in the slot.
  */
 static inline ItemPointer slot_get_ctid(TupleTableSlot *slot)
 {
 	if (TupHasHeapTuple(slot))
 	{
 		Assert(ItemPointerIsValid(&(slot->PRIVATE_tts_heaptuple->t_self)));
 		return &(slot->PRIVATE_tts_heaptuple->t_self);
 	}

 	return &(slot->PRIVATE_tts_synthetic_ctid);
 }

 /*
  * Get an attribute from the tuple table slot.
  */
 static inline Datum slot_getattr(TupleTableSlot *slot, int attnum, bool *isnull)
 {
 	Assert(!TupIsNull(slot));
 	Assert(attnum <= slot->tts_tupleDescriptor->natts);

 	/* System attribute */
 	if(attnum <= 0)
 		return slot_getsysattr(slot, attnum, isnull);

 	/* fast path for virtual tuple */
 	if(TupHasVirtualTuple(slot) && slot->PRIVATE_tts_nvalid >= attnum)
 	{
 		*isnull = slot->PRIVATE_tts_isnull[attnum-1];
 		return slot->PRIVATE_tts_values[attnum-1];
 	}

 	/* Mem tuple: We do not even populate virtual tuple */
 	if(TupHasMemTuple(slot))
 	{
 		Assert(slot->tts_mt_bind);
 		return memtuple_getattr(slot->PRIVATE_tts_memtuple, slot->tts_mt_bind, attnum, isnull);
 	}

 	/* Slow: heap tuple */
 	Assert(TupHasHeapTuple(slot));

 	_slot_getsomeattrs(slot, attnum);
 	Assert(TupHasVirtualTuple(slot) && slot->PRIVATE_tts_nvalid >= attnum);
 	*isnull = slot->PRIVATE_tts_isnull[attnum-1];
 	return slot->PRIVATE_tts_values[attnum-1];
 }

 static inline bool slot_attisnull(TupleTableSlot *slot, int attnum)
 {
 	if(attnum <= 0)
 		return false;

 	if(TupHasHeapTuple(slot))
 		return heap_attisnull_normalattr(slot->PRIVATE_tts_heaptuple, attnum);

 	if(TupHasVirtualTuple(slot) && slot->PRIVATE_tts_nvalid >= attnum)
 		return slot->PRIVATE_tts_isnull[attnum-1];

 	Assert(TupHasMemTuple(slot));
 	return memtuple_attisnull(slot->PRIVATE_tts_memtuple, slot->tts_mt_bind, attnum);
 }

 /*
  * Tuple table data structure: an array of TupleTableSlots.
  */
 typedef struct TupleTableData
 {
 	int			size;			/* size of the table (number of slots) */
 	int			next;			/* next available slot number */
 	TupleTableSlot array[1];	/* VARIABLE LENGTH ARRAY - must be last */
 } TupleTableData;				/* VARIABLE LENGTH STRUCT */

 typedef TupleTableData *TupleTable;

 /* in executor/execTuples.c */
 extern void init_slot(TupleTableSlot *slot, TupleDesc tupdesc);

 extern TupleTable ExecCreateTupleTable(int tableSize);
 extern void ExecDropTupleTable(TupleTable table, bool shouldFree);
 extern TupleTableSlot *MakeSingleTupleTableSlot(TupleDesc tupdesc);
 extern void ExecDropSingleTupleTableSlot(TupleTableSlot *slot);
 extern TupleTableSlot *ExecAllocTableSlot(TupleTable table);
 extern void ExecSetSlotDescriptor(TupleTableSlot *slot, TupleDesc tupdesc);

 extern TupleTableSlot *ExecStoreHeapTuple(HeapTuple tuple,
 			   TupleTableSlot *slot,
 			   Buffer buffer,
 			   bool shouldFree);
 extern TupleTableSlot *ExecStoreMemTuple(MemTuple mtup,
 					  TupleTableSlot *slot,
 					  bool shouldFree);

 extern TupleTableSlot *ExecClearTuple(TupleTableSlot *slot);
 extern TupleTableSlot *ExecStoreVirtualTuple(TupleTableSlot *slot);
 extern TupleTableSlot *ExecStoreAllNullTuple(TupleTableSlot *slot);

 extern HeapTuple ExecCopySlotHeapTuple(TupleTableSlot *slot);
 extern HeapTuple ExecCopySlotHeapTupleTo(TupleTableSlot *slot, MemoryContext pctxt, char *dest, unsigned int *len);
 extern MemTuple ExecCopySlotMemTuple(TupleTableSlot *slot);
 extern MemTuple ExecCopySlotMemTupleTo(TupleTableSlot *slot, MemoryContext pctxt, char *dest, unsigned int *len);

 extern HeapTuple ExecFetchSlotHeapTuple(TupleTableSlot *slot);
 extern MemTuple ExecFetchSlotMemTuple(TupleTableSlot *slot, bool inline_toast);

 extern Datum ExecFetchSlotTupleDatum(TupleTableSlot *slot);

 static inline void *ExecFetchSlotGenericTuple(TupleTableSlot *slot, bool mtup_inline_toast)
 {
 	Assert(!TupIsNull(slot));
 	if (slot->PRIVATE_tts_memtuple == NULL && slot->PRIVATE_tts_heaptuple != NULL)
 		return (void *) slot->PRIVATE_tts_heaptuple;

 	return ExecFetchSlotMemTuple(slot, mtup_inline_toast);
 }

 static inline TupleTableSlot *ExecStoreGenericTuple(void *tup, TupleTableSlot *slot, bool shouldFree)
 {
 	if(is_heaptuple_memtuple((HeapTuple) tup))
 		return ExecStoreMemTuple((MemTuple) tup, slot, shouldFree);

 	return ExecStoreHeapTuple((HeapTuple) tup, slot, InvalidBuffer, shouldFree);
 }

 static inline HeapTuple ExecCopyGenericTuple(TupleTableSlot *slot)
 {
 	Assert(!TupIsNull(slot));
 	if(slot->PRIVATE_tts_heaptuple != NULL && slot->PRIVATE_tts_memtuple == NULL)
 		return ExecCopySlotHeapTuple(slot);
 	return (HeapTuple) ExecCopySlotMemTuple(slot);
 }

 extern TupleTableSlot *ExecCopySlot(TupleTableSlot *dstslot, TupleTableSlot *srcslot);

 extern void ExecModifyMemTuple(TupleTableSlot *slot, Datum *values, bool *isnull, bool *doRepl);
 #endif   /* TUPTABLE_H */
	/*-------------------------------------------------------------------------
	*
	* tuptable.h
	* tuple table support stuff
	*
	*
	* Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
	* Portions Copyright (c) 1994, Regents of the University of California
	*
	* $PostgreSQL: pgsql/src/include/executor/tuptable.h,v 1.36 2006/10/04 00:30:08 momjian Exp $
	*
	*-------------------------------------------------------------------------
	*/
	#ifndef TUPTABLE_H
	#define TUPTABLE_H

	#include "access/htup.h"
	#include "access/tupdesc.h"
	#include "access/heapam.h"
	#include "access/memtup.h"
	#include "storage/buf.h"

	/*----------
	* The executor stores tuples in a "tuple table" which is composed of
	* independent TupleTableSlots. There are several cases we need to handle:
	* 1. physical tuple in a disk buffer page
	* 2. physical tuple constructed in palloc'ed memory
	* 3. "minimal" physical tuple constructed in palloc'ed memory
	* 4. "virtual" tuple consisting of Datum/isnull arrays
	*
	* The first two cases are similar in that they both deal with "materialized"
	* tuples, but resource management is different. For a tuple in a disk page
	* we need to hold a pin on the buffer until the TupleTableSlot's reference
	* to the tuple is dropped; while for a palloc'd tuple we usually want the
	* tuple pfree'd when the TupleTableSlot's reference is dropped.
	*
	* A "minimal" tuple is handled similarly to a palloc'd regular tuple.
	* At present, minimal tuples never are stored in buffers, so there is no
	* parallel to case 1. Note that a minimal tuple has no "system columns".
	* (Actually, it could have an OID, but we have no need to access the OID.)
	*
	* A "virtual" tuple is an optimization used to minimize physical data
	* copying in a nest of plan nodes. Any pass-by-reference Datums in the
	* tuple point to storage that is not directly associated with the
	* TupleTableSlot; generally they will point to part of a tuple stored in
	* a lower plan node's output TupleTableSlot, or to a function result
	* constructed in a plan node's per-tuple econtext. It is the responsibility
	* of the generating plan node to be sure these resources are not released
	* for as long as the virtual tuple needs to be valid. We only use virtual
	* tuples in the result slots of plan nodes --- tuples to be copied anywhere
	* else need to be "materialized" into physical tuples. Note also that a
	* virtual tuple does not have any "system columns".
	*
	* The Datum/isnull arrays of a TupleTableSlot serve double duty. When the
	* slot contains a virtual tuple, they are the authoritative data. When the
	* slot contains a physical tuple, the arrays contain data extracted from
	* the tuple. (In this state, any pass-by-reference Datums point into
	* the physical tuple.) The extracted information is built "lazily",
	* ie, only as needed. This serves to avoid repeated extraction of data
	* from the physical tuple.
	*
	* A TupleTableSlot can also be "empty", holding no valid data. This is
	* the only valid state for a freshly-created slot that has not yet had a
	* tuple descriptor assigned to it. In this state, tts_isempty must be
	* TRUE, tts_shouldFree FALSE, tts_tuple NULL, tts_buffer InvalidBuffer,
	* and tts_nvalid zero.
	*
	* The tupleDescriptor is simply referenced, not copied, by the TupleTableSlot
	* code. The caller of ExecSetSlotDescriptor() is responsible for providing
	* a descriptor that will live as long as the slot does. (Typically, both
	* slots and descriptors are in per-query memory and are freed by memory
	* context deallocation at query end; so it's not worth providing any extra
	* mechanism to do more. However, the slot will increment the tupdesc
	* reference count if a reference-counted tupdesc is supplied.)
	*
	* When tts_shouldFree is true, the physical tuple is "owned" by the slot
	* and should be freed when the slot's reference to the tuple is dropped.
	*
	* If tts_buffer is not InvalidBuffer, then the slot is holding a pin
	* on the indicated buffer page; drop the pin when we release the
	* slot's reference to that buffer. (tts_shouldFree should always be
	* false in such a case, since presumably tts_tuple is pointing at the
	* buffer page.)
	*
	* tts_nvalid indicates the number of valid columns in the tts_values/isnull
	* arrays. When the slot is holding a "virtual" tuple this must be equal
	* to the descriptor's natts. When the slot is holding a physical tuple
	* this is equal to the number of columns we have extracted (we always
	* extract columns from left to right, so there are no holes).
	*
	* tts_values/tts_isnull are allocated when a descriptor is assigned to the
	* slot; they are of length equal to the descriptor's natts.
	*
	* tts_mintuple must always be NULL if the slot does not hold a "minimal"
	* tuple. When it does, tts_mintuple points to the actual MinimalTupleData
	* object (the thing to be pfree'd if tts_shouldFree is true). In this case
	* tts_tuple points at tts_minhdr and the fields of that are set correctly
	* for access to the minimal tuple; in particular, tts_minhdr.t_data points
	* MINIMAL_TUPLE_OFFSET bytes before tts_mintuple. (tts_mintuple is therefore
	* redundant, but for code simplicity we store it explicitly anyway.) This
	* case otherwise behaves identically to the regular-physical-tuple case.
	*
	* tts_slow/tts_off are saved state for slot_deform_tuple, and should not
	* be touched by any other code.
	*----------
	*/

	/* tts_flags */
	#define TTS_ISEMPTY 1
	#define TTS_SHOULDFREE 2
	#define TTS_VIRTUAL 4

	typedef struct TupleTableSlot
	{
	NodeTag type; /* vestigial ... allows IsA tests */
	int PRIVATE_tts_flags; /* TTS_xxx flags */

	/* Heap tuple stuff */
	HeapTuple PRIVATE_tts_heaptuple;
	void *PRIVATE_tts_htup_buf;
	uint32 PRIVATE_tts_htup_buf_len;

	/* Mem tuple stuff */
	MemTuple PRIVATE_tts_memtuple;
	void *PRIVATE_tts_mtup_buf;
	uint32 PRIVATE_tts_mtup_buf_len;
	ItemPointerData PRIVATE_tts_synthetic_ctid; /* needed if memtuple is stored on disk */

	/* Virtual tuple stuff */
	int PRIVATE_tts_nvalid; /* number of valid virtual tup entries */
	long PRIVATE_tts_off; /* hack to remember state of last decoding. */
	bool PRIVATE_tts_slow; /* hack to remember state of last decoding. */
	Datum PRIVATE_tts_values; / virtual tuple values */
	bool PRIVATE_tts_isnull; / virtual tuple nulls */

	Datum PRIVATE_tb; /* Vectorized Execution TupleBatch */

	TupleDesc tts_tupleDescriptor; /* slot's tuple descriptor */
	MemTupleBinding tts_mt_bind; / mem tuple's binding */
	MemoryContext tts_mcxt; /* slot itself is in this context */
	Buffer tts_buffer; /* tuple's buffer, or InvalidBuffer */

	/* System attributes */
	Oid tts_tableOid;
	} TupleTableSlot;

	static inline bool TupIsNull(TupleTableSlot *slot)
	{
	return (slot == NULL \|\| (slot->PRIVATE_tts_flags & TTS_ISEMPTY) != 0);
	}
	static inline void TupClearIsEmpty(TupleTableSlot *slot)
	{
	slot->PRIVATE_tts_flags &= (~TTS_ISEMPTY);
	}
	static inline bool TupShouldFree(TupleTableSlot *slot)
	{
	Assert(slot);
	return ((slot->PRIVATE_tts_flags & TTS_SHOULDFREE) != 0);
	}
	static inline void TupSetShouldFree(TupleTableSlot *slot)
	{
	slot->PRIVATE_tts_flags \|= TTS_SHOULDFREE;
	}
	static inline void TupClearShouldFree(TupleTableSlot *slot)
	{
	slot->PRIVATE_tts_flags &= (~TTS_SHOULDFREE);
	}
	static inline bool TupHasHeapTuple(TupleTableSlot *slot)
	{
	Assert(slot);
	return slot->PRIVATE_tts_heaptuple != NULL;
	}
	static inline bool TupHasMemTuple(TupleTableSlot *slot)
	{
	Assert(slot);
	return slot->PRIVATE_tts_memtuple != NULL;
	}
	static inline bool TupHasVirtualTuple(TupleTableSlot *slot)
	{
	Assert(slot);
	return (slot->PRIVATE_tts_flags & TTS_VIRTUAL) ? true : false;
	}
	static inline HeapTuple TupGetHeapTuple(TupleTableSlot *slot)
	{
	Assert(TupHasHeapTuple(slot));
	Assert(!is_heaptuple_memtuple(slot->PRIVATE_tts_heaptuple));
	return slot->PRIVATE_tts_heaptuple;
	}
	static inline MemTuple TupGetMemTuple(TupleTableSlot *slot)
	{
	Assert(TupHasMemTuple(slot));
	return slot->PRIVATE_tts_memtuple;
	}

	static inline void free_heaptuple_memtuple(TupleTableSlot *slot)
	{
	if(TupShouldFree(slot))
	{
	if(slot->PRIVATE_tts_heaptuple && slot->PRIVATE_tts_heaptuple != slot->PRIVATE_tts_htup_buf)
	pfree(slot->PRIVATE_tts_heaptuple);

	if(slot->PRIVATE_tts_memtuple && slot->PRIVATE_tts_memtuple != slot->PRIVATE_tts_mtup_buf)
	pfree(slot->PRIVATE_tts_memtuple);
	}

	slot->PRIVATE_tts_heaptuple = NULL;
	slot->PRIVATE_tts_memtuple = NULL;
	}

	static inline void TupSetVirtualTuple(TupleTableSlot *slot)
	{
	Assert(slot);
	slot->PRIVATE_tts_flags \|= TTS_VIRTUAL;
	}

	static inline void TupSetVirtualTupleNValid(TupleTableSlot *slot, int nvalid)
	{
	free_heaptuple_memtuple(slot);
	slot->PRIVATE_tts_flags = TTS_VIRTUAL;
	slot->PRIVATE_tts_nvalid = nvalid;
	}

	static inline Datum slot_get_values(TupleTableSlot slot)
	{
	return slot->PRIVATE_tts_values;
	}

	static inline bool slot_get_isnull(TupleTableSlot slot)
	{
	return slot->PRIVATE_tts_isnull;
	}

	extern void _slot_getsomeattrs(TupleTableSlot *slot, int attnum);
	static inline void slot_getsomeattrs(TupleTableSlot *slot, int attnum)
	{

	if(TupHasVirtualTuple(slot))
	{
	if(slot->PRIVATE_tts_nvalid >= attnum)
	return;
	}

	if(TupHasMemTuple(slot))
	{
	int i;
	for(i=0; i<attnum; ++i)
	slot->PRIVATE_tts_values[i] = memtuple_getattr(
	slot->PRIVATE_tts_memtuple, slot->tts_mt_bind,
	i+1, &(slot->PRIVATE_tts_isnull[i]));

	TupSetVirtualTuple(slot);
	slot->PRIVATE_tts_nvalid = attnum;
	return;
	}

	_slot_getsomeattrs(slot, attnum);
	TupSetVirtualTuple(slot);
	}


	static inline void slot_getallattrs(TupleTableSlot *slot)
	{
	slot_getsomeattrs(slot, slot->tts_tupleDescriptor->natts);
	}

	extern Datum slot_getsysattr(TupleTableSlot slot, int attnum, bool isnull);

	/*
	* Set the synthetic ctid to a given ctid value.
	*
	* If the slot contains a memtuple or a virtual tuple, the PRIVATE_tts_synthetic_ctid
	* is set to the given ctid value. If the slot contains a heap tuple, then t_self
	* in the heap tuple is set to the given ctid value.
	*
	* This function will set both PRIVATE_tts_synthetic_ctid and heaptuple->t_self when
	* both heap tuple and memtuple or virtual tuple are presented.
	*/
	static inline void slot_set_ctid(TupleTableSlot *slot, ItemPointer new_ctid)
	{
	Assert(slot);

	if (TupHasHeapTuple(slot))
	{
	HeapTuple tuple = TupGetHeapTuple(slot);
	tuple->t_self = *new_ctid;
	}

	if (TupHasMemTuple(slot) \|\| TupHasVirtualTuple(slot))
	slot->PRIVATE_tts_synthetic_ctid = *new_ctid;
	}

	extern void slot_set_ctid_from_fake(TupleTableSlot slot, ItemPointerData fake_ctid);

	/*
	* Retrieve the synthetic ctid value from the slot.
	*
	* This function assumes that the PRIVATE_tts_synthetic_ctid and heaptuple->t_self
	* are in sync if both of them are presented in the slot.
	*/
	static inline ItemPointer slot_get_ctid(TupleTableSlot *slot)
	{
	if (TupHasHeapTuple(slot))
	{
	Assert(ItemPointerIsValid(&(slot->PRIVATE_tts_heaptuple->t_self)));
	return &(slot->PRIVATE_tts_heaptuple->t_self);
	}

	return &(slot->PRIVATE_tts_synthetic_ctid);
	}

	/*
	* Get an attribute from the tuple table slot.
	*/
	static inline Datum slot_getattr(TupleTableSlot slot, int attnum, bool isnull)
	{
	Assert(!TupIsNull(slot));
	Assert(attnum <= slot->tts_tupleDescriptor->natts);

	/* System attribute */
	if(attnum <= 0)
	return slot_getsysattr(slot, attnum, isnull);

	/* fast path for virtual tuple */
	if(TupHasVirtualTuple(slot) && slot->PRIVATE_tts_nvalid >= attnum)
	{
	*isnull = slot->PRIVATE_tts_isnull[attnum-1];
	return slot->PRIVATE_tts_values[attnum-1];
	}

	/* Mem tuple: We do not even populate virtual tuple */
	if(TupHasMemTuple(slot))
	{
	Assert(slot->tts_mt_bind);
	return memtuple_getattr(slot->PRIVATE_tts_memtuple, slot->tts_mt_bind, attnum, isnull);
	}

	/* Slow: heap tuple */
	Assert(TupHasHeapTuple(slot));

	_slot_getsomeattrs(slot, attnum);
	Assert(TupHasVirtualTuple(slot) && slot->PRIVATE_tts_nvalid >= attnum);
	*isnull = slot->PRIVATE_tts_isnull[attnum-1];
	return slot->PRIVATE_tts_values[attnum-1];
	}

	static inline bool slot_attisnull(TupleTableSlot *slot, int attnum)
	{
	if(attnum <= 0)
	return false;

	if(TupHasHeapTuple(slot))
	return heap_attisnull_normalattr(slot->PRIVATE_tts_heaptuple, attnum);

	if(TupHasVirtualTuple(slot) && slot->PRIVATE_tts_nvalid >= attnum)
	return slot->PRIVATE_tts_isnull[attnum-1];

	Assert(TupHasMemTuple(slot));
	return memtuple_attisnull(slot->PRIVATE_tts_memtuple, slot->tts_mt_bind, attnum);
	}

	/*
	* Tuple table data structure: an array of TupleTableSlots.
	*/
	typedef struct TupleTableData
	{
	int size; /* size of the table (number of slots) */
	int next; /* next available slot number */
	TupleTableSlot array[1]; /* VARIABLE LENGTH ARRAY - must be last */
	} TupleTableData; /* VARIABLE LENGTH STRUCT */

	typedef TupleTableData *TupleTable;

	/* in executor/execTuples.c */
	extern void init_slot(TupleTableSlot *slot, TupleDesc tupdesc);

	extern TupleTable ExecCreateTupleTable(int tableSize);
	extern void ExecDropTupleTable(TupleTable table, bool shouldFree);
	extern TupleTableSlot *MakeSingleTupleTableSlot(TupleDesc tupdesc);
	extern void ExecDropSingleTupleTableSlot(TupleTableSlot *slot);
	extern TupleTableSlot *ExecAllocTableSlot(TupleTable table);
	extern void ExecSetSlotDescriptor(TupleTableSlot *slot, TupleDesc tupdesc);

	extern TupleTableSlot *ExecStoreHeapTuple(HeapTuple tuple,
	TupleTableSlot *slot,
	Buffer buffer,
	bool shouldFree);
	extern TupleTableSlot *ExecStoreMemTuple(MemTuple mtup,
	TupleTableSlot *slot,
	bool shouldFree);

	extern TupleTableSlot ExecClearTuple(TupleTableSlot slot);
	extern TupleTableSlot ExecStoreVirtualTuple(TupleTableSlot slot);
	extern TupleTableSlot ExecStoreAllNullTuple(TupleTableSlot slot);

	extern HeapTuple ExecCopySlotHeapTuple(TupleTableSlot *slot);
	extern HeapTuple ExecCopySlotHeapTupleTo(TupleTableSlot slot, MemoryContext pctxt, char dest, unsigned int *len);
	extern MemTuple ExecCopySlotMemTuple(TupleTableSlot *slot);
	extern MemTuple ExecCopySlotMemTupleTo(TupleTableSlot slot, MemoryContext pctxt, char dest, unsigned int *len);

	extern HeapTuple ExecFetchSlotHeapTuple(TupleTableSlot *slot);
	extern MemTuple ExecFetchSlotMemTuple(TupleTableSlot *slot, bool inline_toast);

	extern Datum ExecFetchSlotTupleDatum(TupleTableSlot *slot);

	static inline void ExecFetchSlotGenericTuple(TupleTableSlot slot, bool mtup_inline_toast)
	{
	Assert(!TupIsNull(slot));
	if (slot->PRIVATE_tts_memtuple == NULL && slot->PRIVATE_tts_heaptuple != NULL)
	return (void *) slot->PRIVATE_tts_heaptuple;

	return ExecFetchSlotMemTuple(slot, mtup_inline_toast);
	}

	static inline TupleTableSlot ExecStoreGenericTuple(void tup, TupleTableSlot *slot, bool shouldFree)
	{
	if(is_heaptuple_memtuple((HeapTuple) tup))
	return ExecStoreMemTuple((MemTuple) tup, slot, shouldFree);

	return ExecStoreHeapTuple((HeapTuple) tup, slot, InvalidBuffer, shouldFree);
	}

	static inline HeapTuple ExecCopyGenericTuple(TupleTableSlot *slot)
	{
	Assert(!TupIsNull(slot));
	if(slot->PRIVATE_tts_heaptuple != NULL && slot->PRIVATE_tts_memtuple == NULL)
	return ExecCopySlotHeapTuple(slot);
	return (HeapTuple) ExecCopySlotMemTuple(slot);
	}

	extern TupleTableSlot ExecCopySlot(TupleTableSlot dstslot, TupleTableSlot *srcslot);

	extern void ExecModifyMemTuple(TupleTableSlot slot, Datum values, bool isnull, bool doRepl);
	#endif /* TUPTABLE_H */