本节介绍heapam_tuple_insert函数的代码流程

相关数据结构

结构体中有些成员可能目前难以理解，暂时先列出来，先把当前用到的成员能搞明白就可以。

// src/include/executor/tuptable.h

typedef struct TupleTableSlot
{
	nodeTag		type;
#define FIELDNO_TUPLETABLESLOT_FLAGS 1
	uint16		tts_flags;		
#define FIELDNO_TUPLETABLESLOT_NVALID 2
	AttrNumber	tts_nvalid;		
	const TupleTableSlotOps *const tts_ops; 
#define FIELDNO_TUPLETABLESLOT_TUPLEDESCRIPTOR 4
	TupleDesc	tts_tupleDescriptor;	
#define FIELDNO_TUPLETABLESLOT_VALUES 5
	Datum	   *tts_values;		
#define FIELDNO_TUPLETABLESLOT_ISNULL 6
	bool	   *tts_isnull;		
	MemoryContext tts_mcxt;		
	ItemPointerData tts_tid;	
	Oid			tts_tableOid;	
} TupleTableSlot;

static void
heapam_tuple_insert(Relation relation, TupleTableSlot *slot, CommandId cid,
					int options, BulkInsertState bistate);

heapam_tuple_insert函数

HeapTuple	tuple = ExecFetchSlotHeapTuple(slot, true, &shouldFree);


slot->tts_tableOid = RelationGetRelid(relation);
tuple->t_tableOid = slot->tts_tableOid;


heap_insert(relation, tuple, cid, options, bistate);
ItemPointerCopy(&tuple->t_self, &slot->tts_tid);


if (shouldFree)
	pfree(tuple);