Function deparseExplicitTargetList

contrib/postgres_fdw/deparse.c:1443–1472

* Deparse given targetlist and append it to context->buf. * * tlist is list of TargetEntry's which in turn contain Var nodes. * * retrieved_attrs is the list of continuously increasing integers starting * from 1. It has same number of entries as tlist. * * This is used for both SELECT and RETURNING targetlists; the is_returning * parameter is true only for a RETURNING targetlist. */

 * parameter is true only for a RETURNING targetlist.
 */
static void
deparseExplicitTargetList(List *tlist,
						  bool is_returning,
						  List **retrieved_attrs,
						  deparse_expr_cxt *context)
{
	ListCell   *lc;
	StringInfo	buf = context->buf;
	int			i = 0;

	*retrieved_attrs = NIL;

	foreach(lc, tlist)
	{
		TargetEntry *tle = lfirst_node(TargetEntry, lc);

		if (i > 0)
			appendStringInfoString(buf, ", ");
		else if (is_returning)
			appendStringInfoString(buf, " RETURNING ");

		deparseExpr((Expr *) tle->expr, context);

		*retrieved_attrs = lappend_int(*retrieved_attrs, i + 1);
		i++;
	}

	if (i == 0 && !is_returning)
		appendStringInfoString(buf, "NULL");
}

/*
 * Emit expressions specified in the given relation's reltarget.