diff --git a/doc/src/sgml/ref/psql-ref.sgml b/doc/src/sgml/ref/psql-ref.sgml
index f8eb6cfddde..0aa9ca47358 100644
--- a/doc/src/sgml/ref/psql-ref.sgml
+++ b/doc/src/sgml/ref/psql-ref.sgml
@@ -1,5 +1,5 @@
@@ -1502,11 +1502,14 @@ Access permissions for database "test"
-v, --variable, --set assignment
- Performs a variable assignment, like the \set internal command.
- Note that you must separate name and value, if any, by an equal sign on the command
- line. To unset a variable, leave off the equal sign. These assignments are done
- during a very early state of start-up, so variables reserved for internal purposes
- might get overwritten later.
+ Performs a variable assignment, like the \set
+ internal command. Note that you must separate name and value,
+ if any, by an equal sign on the command line. To unset a
+ variable, leave off the equal sign. To just set a variable
+ without a value, use the equal sign but leave off the value.
+ These assignments are done during a very early stage of
+ start-up, so variables reserved for internal purposes might get
+ overwritten later.