diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,5 +1,10 @@
 # Changelog for persistent
 
+## 2.13.0.1
+
+* [#1268](https://github.com/yesodweb/persistent/pull/1268)
+    * Show `keyFromValues` error
+
 ## 2.13.0.0
 
 * [#1244](https://github.com/yesodweb/persistent/pull/1244)
@@ -11,7 +16,7 @@
       Please use `mkEntityDefList` instead.
     * `EntityDef` will now include fields marked `MigrationOnly` and
       `SafeToRemove`. Beforehand, those were filtered out, and `mkMigrate`
-      applied. The function `getEntityFields` wll only return fields defined on
+      applied. The function `getEntityFields` will only return fields defined on
       the Haskell type - for all columns, see `getEntityFieldsDatabase`.
 * [#1225](https://github.com/yesodweb/persistent/pull/1225)
     * The fields and constructor for `SqlBackend` are no longer exported by
@@ -26,16 +31,18 @@
       directly, use `mkSqlBackend` and the datatype `MkSqlBackendArgs`. The
       `MkSqlBackendArgs` record has the same field names as the `SqlBackend`, so
       the translation is easy:
-      ```diff
-- SqlBackend
-+ mkSqlBackend MkSqlBackendArgs
-    { connInsertSql = ...
-    , connCommit = ...
-    , connEscapeFieldName = ...
-    , connEscapeTableName = ...
-    , etc
-    }
-      ```
+
+        ```diff
+        - SqlBackend
+        + mkSqlBackend MkSqlBackendArgs
+            { connInsertSql = ...
+            , connCommit = ...
+            , connEscapeFieldName = ...
+            , connEscapeTableName = ...
+            , etc
+            }
+        ```
+
       Some fields were omitted in `MkSqlBackendArgs`. These fields are
       *optional* - they provide enhanced or backend-specific functionality. For
       these, use the setter functions like `setConnUpsertSql`.
diff --git a/Database/Persist/Sql/Util.hs b/Database/Persist/Sql/Util.hs
--- a/Database/Persist/Sql/Util.hs
+++ b/Database/Persist/Sql/Util.hs
@@ -188,7 +188,8 @@
         case fromPersistValues xs of
             Left e -> Left e
             Right xs' -> case keyFromValues keyvals of
-                Left _ -> error "fromPersistValuesComposite': keyFromValues failed"
+                Left err -> error $ "fromPersistValuesComposite': keyFromValues failed with error: "
+                    <> T.unpack err
                 Right key -> Right (Entity key xs')
 
 
diff --git a/persistent.cabal b/persistent.cabal
--- a/persistent.cabal
+++ b/persistent.cabal
@@ -1,5 +1,5 @@
 name:            persistent
-version:         2.13.0.0
+version:         2.13.0.1
 license:         MIT
 license-file:    LICENSE
 author:          Michael Snoyman <michael@snoyman.com>