diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,5 +1,9 @@
 <!-- -*- Markdown -*- -->
 
+## 0.6.4.2
+
+- add an upper bound of version constraint.
+
 ## 0.6.4.1
 
 - apply integrated namespace with new exported symbols.
diff --git a/relational-query-HDBC.cabal b/relational-query-HDBC.cabal
--- a/relational-query-HDBC.cabal
+++ b/relational-query-HDBC.cabal
@@ -1,5 +1,5 @@
 name:                relational-query-HDBC
-version:             0.6.4.1
+version:             0.6.4.2
 synopsis:            HDBC instance of relational-query and typed query interface for HDBC
 description:         This package contains the HDBC instance of relational-query and
                      the typed query interface for HDBC.
@@ -58,7 +58,7 @@
 
                        , names-th
                        , persistable-record >= 0.5
-                       , relational-query >= 0.9.5
+                       , relational-query >= 0.9.5 && < 0.10
                        , relational-schemas
                        , HDBC >=2
                        , HDBC-session