Function QueryListGetPrimaryStmt

src/backend/utils/cache/plancache.c:1832–1845

* QueryListGetPrimaryStmt * Get the "primary" stmt within a list, ie, the one marked canSetTag. * * Returns NULL if no such stmt. If multiple queries within the list are * marked canSetTag, returns the first one. Neither of these cases should * occur in present usages of this function. */

 * occur in present usages of this function.
 */
static Query *
QueryListGetPrimaryStmt(List *stmts)
{
	ListCell   *lc;

	foreach(lc, stmts)
	{
		Query	   *stmt = lfirst_node(Query, lc);

		if (stmt->canSetTag)
			return stmt;
	}
	return NULL;
}

/*
 * AcquireExecutorLocks: acquire locks needed for execution of a cached plan;