diff --git a/doc/src/sgml/ref/create_rule.sgml b/doc/src/sgml/ref/create_rule.sgml
index dbf4c93784..76029abf51 100644
--- a/doc/src/sgml/ref/create_rule.sgml
+++ b/doc/src/sgml/ref/create_rule.sgml
@@ -59,15 +59,17 @@ CREATE [ OR REPLACE ] RULE name AS
- Presently, ON SELECT rules must be unconditional
- INSTEAD rules and must have actions that consist
- of a single SELECT command. Thus, an
- ON SELECT rule effectively turns the table into
- a view, whose visible contents are the rows returned by the rule's
- SELECT command rather than whatever had been
- stored in the table (if anything). It is considered better style
- to write a CREATE VIEW command than to create a
- real table and define an ON SELECT rule for it.
+ Presently, ON SELECT rules can only be attached
+ to views. (Attaching one to a table converts the table into a view.)
+ Such a rule must be named "_RETURN",
+ must be an unconditional INSTEAD rule, and must have
+ an action that consists of a single SELECT command.
+ This command defines the visible contents of the view. (The view
+ itself is basically a dummy table with no storage.) It's best to
+ regard such a rule as an implementation detail. While a view can be
+ redefined via CREATE OR REPLACE RULE "_RETURN" AS
+ ..., it's better style to use CREATE OR REPLACE
+ VIEW.