Function MultiExecPrivateHash

src/backend/executor/nodeHash.c:166–256

---------------------------------------------------------------- * MultiExecPrivateHash * * parallel-oblivious version, building a backend-private * hash table and (if necessary) batch files. * ---------------------------------------------------------------- */

 * ----------------------------------------------------------------
 */
static void
MultiExecPrivateHash(HashState *node)
{
	PlanState  *outerNode;
	List	   *hashkeys;
	HashJoinTable hashtable;
	TupleTableSlot *slot;
	ExprContext *econtext;
	uint32		hashvalue;

	/*
	 * get state info from node
	 */
	outerNode = outerPlanState(node);
	hashtable = node->hashtable;

	/*
	 * set expression context
	 */
	hashkeys = node->hashkeys;
	econtext = node->ps.ps_ExprContext;

	SIMPLE_FAULT_INJECTOR("multi_exec_hash_large_vmem");

	/*
	 * Get all tuples from the node below the Hash node and insert into the
	 * hash table (or temp files).
	 */
	for (;;)
	{
		slot = ExecProcNode(outerNode);
		if (TupIsNull(slot))
		{
			if (gp_enable_runtime_filter_pushdown && node->filters)
				PushdownRuntimeFilter(node);
			break;
		}

		if (gp_enable_runtime_filter_pushdown && node->filters)
			AddTupleValuesIntoRF(node, slot);

		/* We have to compute the hash value */
		econtext->ecxt_outertuple = slot;
		bool hashkeys_null = false;
		if (ExecHashGetHashValue(node, hashtable, econtext, hashkeys,
								 false, hashtable->keepNulls,
								 &hashvalue, &hashkeys_null))
		{
			int			bucketNumber;

			bucketNumber = ExecHashGetSkewBucket(hashtable, hashvalue);
			if (bucketNumber != INVALID_SKEW_BUCKET_NO)
			{
				/* It's a skew tuple, so put it into that hash table */
				ExecHashSkewTableInsert(node, hashtable, slot, hashvalue,
										bucketNumber);
				hashtable->skewTuples += 1;
			}