Function AfterTriggerEndQuery

src/backend/commands/trigger.c:4768–4849

---------- * AfterTriggerEndQuery() * * Called after one query has been completely processed. At this time * we invoke all AFTER IMMEDIATE trigger events queued by the query, and * transfer deferred trigger events to the global deferred-trigger list. * * Note that this must be called BEFORE closing down the executor * with ExecutorEnd, because we make use of the EState's info about * targ

 * ----------
 */
void
AfterTriggerEndQuery(EState *estate)
{
	AfterTriggersQueryData *qs;

	/* Must be inside a query, too */
	Assert(afterTriggers.query_depth >= 0);

	/*
	 * If we never even got as far as initializing the event stack, there
	 * certainly won't be any events, so exit quickly.
	 */
	if (afterTriggers.query_depth >= afterTriggers.maxquerydepth)
	{
		afterTriggers.query_depth--;
		return;
	}

	/*
	 * Process all immediate-mode triggers queued by the query, and move the
	 * deferred ones to the main list of deferred events.
	 *
	 * Notice that we decide which ones will be fired, and put the deferred
	 * ones on the main list, before anything is actually fired.  This ensures
	 * reasonably sane behavior if a trigger function does SET CONSTRAINTS ...
	 * IMMEDIATE: all events we have decided to defer will be available for it
	 * to fire.
	 *
	 * We loop in case a trigger queues more events at the same query level.
	 * Ordinary trigger functions, including all PL/pgSQL trigger functions,
	 * will instead fire any triggers in a dedicated query level.  Foreign key
	 * enforcement triggers do add to the current query level, thanks to their
	 * passing fire_triggers = false to SPI_execute_snapshot().  Other
	 * C-language triggers might do likewise.
	 *
	 * If we find no firable events, we don't have to increment
	 * firing_counter.
	 */
	qs = &afterTriggers.query_stack[afterTriggers.query_depth];

	for (;;)
	{
		if (afterTriggerMarkEvents(&qs->events, &afterTriggers.events, true))
		{
			CommandId	firing_id = afterTriggers.firing_counter++;
			AfterTriggerEventChunk *oldtail = qs->events.tail;

			if (afterTriggerInvokeEvents(&qs->events, firing_id, estate, false))
				break;			/* all fired */

			/*
			 * Firing a trigger could result in query_stack being repalloc'd,
			 * so we must recalculate qs after each afterTriggerInvokeEvents
			 * call.  Furthermore, it's unsafe to pass delete_ok = true here,
			 * because that could cause afterTriggerInvokeEvents to try to
			 * access qs->events after the stack has been repalloc'd.
			 */
			qs = &afterTriggers.query_stack[afterTriggers.query_depth];