diff --git a/doc/src/sgml/ref/create_table.sgml b/doc/src/sgml/ref/create_table.sgml
index adfcd13ff0..2c5e14caf2 100644
--- a/doc/src/sgml/ref/create_table.sgml
+++ b/doc/src/sgml/ref/create_table.sgml
@@ -1,5 +1,5 @@
@@ -293,7 +293,10 @@ and table_constraint is:
CONSTRAINT constraint_name
- An optional name for a column or table constraint. If not specified,
+ An optional name for a column or table constraint. If the
+ constraint is violated, the constraint name is present in error messages,
+ so constraint names like "col must be positive" can be used to communicate
+ helpful constraint information to client applications. If not specified,
the system generates a name.