Function fireRIRrules

src/backend/rewrite/rewriteHandler.c:2050–2330

* fireRIRrules - * Apply all RIR rules on each rangetable entry in the given query * * activeRIRs is a list of the OIDs of views we're already processing RIR * rules for, used to detect/reject recursion. */

 * rules for, used to detect/reject recursion.
 */
static Query *
fireRIRrules(Query *parsetree, List *activeRIRs)
{
	int			origResultRelation = parsetree->resultRelation;
	int			rt_index;
	ListCell   *lc;

	/*
	 * Expand SEARCH and CYCLE clauses in CTEs.
	 *
	 * This is just a convenient place to do this, since we are already
	 * looking at each Query.
	 */
	foreach(lc, parsetree->cteList)
	{
		CommonTableExpr *cte = lfirst_node(CommonTableExpr, lc);

		if (cte->search_clause || cte->cycle_clause)
		{
			cte = rewriteSearchAndCycle(cte);
			lfirst(lc) = cte;
		}
	}

	/*
	 * don't try to convert this into a foreach loop, because rtable list can
	 * get changed each time through...
	 */
	rt_index = 0;
	while (rt_index < list_length(parsetree->rtable))
	{
		RangeTblEntry *rte;
		Relation	rel;
		List	   *locks;
		RuleLock   *rules;
		RewriteRule *rule;
		int			i;

		++rt_index;

		rte = rt_fetch(rt_index, parsetree->rtable);

		/*
		 * A subquery RTE can't have associated rules, so there's nothing to
		 * do to this level of the query, but we must recurse into the
		 * subquery to expand any rule references in it.
		 */
		if (rte->rtekind == RTE_SUBQUERY || rte->rtekind == RTE_TABLEFUNCTION)
		{
			rte->subquery = fireRIRrules(rte->subquery, activeRIRs);
			continue;
		}

		/*
		 * Joins and other non-relation RTEs can be ignored completely.
		 */
		if (rte->rtekind != RTE_RELATION)
			continue;