Function ExecReScanAppend

src/backend/executor/nodeAppend.c:421–487

}

void
ExecReScanAppend(AppendState *node)
{
	int			nasyncplans = node->as_nasyncplans;
	int			i;

	/*
	 * If any PARAM_EXEC Params used in pruning expressions have changed, then
	 * we'd better unset the valid subplans so that they are reselected for
	 * the new parameter values.
	 */
	if (node->as_prune_state &&
		bms_overlap(node->ps.chgParam,
					node->as_prune_state->execparamids))
	{
		bms_free(node->as_valid_subplans);
		node->as_valid_subplans = NULL;
		if (nasyncplans > 0)
		{
			bms_free(node->as_valid_asyncplans);
			node->as_valid_asyncplans = NULL;
		}
	}

	for (i = 0; i < node->as_nplans; i++)
	{
		PlanState  *subnode = node->appendplans[i];

		/*
		 * ExecReScan doesn't know about my subplans, so I have to do
		 * changed-parameter signaling myself.
		 */
		if (node->ps.chgParam != NULL)
			UpdateChangedParamSet(subnode, node->ps.chgParam);

		/*
		 * If chgParam of subnode is not null then plan will be re-scanned by
		 * first ExecProcNode or by first ExecAsyncRequest.
		 */
		if (subnode->chgParam == NULL)
			ExecReScan(subnode);
	}

	/* Reset async state */
	if (nasyncplans > 0)
	{
		i = -1;
		while ((i = bms_next_member(node->as_asyncplans, i)) >= 0)
		{
			AsyncRequest *areq = node->as_asyncrequests[i];

			areq->callback_pending = false;
			areq->request_complete = false;
			areq->result = NULL;
		}

		node->as_nasyncresults = 0;
		node->as_nasyncremain = 0;