diff --git a/src/Yam/Transaction/ODBC.hs b/src/Yam/Transaction/ODBC.hs
--- a/src/Yam/Transaction/ODBC.hs
+++ b/src/Yam/Transaction/ODBC.hs
@@ -20,7 +20,7 @@
     let mayMap = do map <- extra ds
                     M.lookup "NLS_LANG" map
     case mayMap of
-      Nothing -> error "DataSource extra.NLS_LANG not set"
+      Nothing -> throwM $ DataSourceConfigNotFound "extra.NLS_LANG"
       Just m  -> liftIO $ setEnv "NLS_LANG" $ cs m
     runLoggingT (withODBCPool (toDbTp $ symbolVal $ toP p) (cs $ conn ds) (thread ds) (lift.a)) logger
     where toP :: KnownSymbol db => Proxy (ODBC db) -> Proxy db
diff --git a/yam-transaction-odbc.cabal b/yam-transaction-odbc.cabal
--- a/yam-transaction-odbc.cabal
+++ b/yam-transaction-odbc.cabal
@@ -1,5 +1,5 @@
 name:                yam-transaction-odbc
-version:             0.1.6
+version:             0.1.7
 description:         Transaction ODBC Plugin
 homepage:            https://github.com/leptonyu/yam/tree/master/yam-transaction-odbc#readme
 license:             BSD3