diff --git a/doc/src/sgml/ref/create_rule.sgml b/doc/src/sgml/ref/create_rule.sgml
index d3212b5..22b46e2 100644
--- a/doc/src/sgml/ref/create_rule.sgml
+++ b/doc/src/sgml/ref/create_rule.sgml
@@ -24,6 +24,9 @@ PostgreSQL documentation
CREATE [ OR REPLACE ] RULE name AS ON event
TO table_name [ WHERE condition ]
DO [ ALSO | INSTEAD ] { NOTHING | command | ( command ; command ... ) }
+
+where event can be one of:
+ { INSERT | UPDATE | DELETE | SELECT}