diff --git a/zh-cn/application-dev/database/database-relational-guidelines.md b/zh-cn/application-dev/database/database-relational-guidelines.md
index 3a10ebb1d43ba88f9b4ff788232163c0b1e8c9c7..696047b7eba4195b8154cfed2c46639279fb52e4 100644
--- a/zh-cn/application-dev/database/database-relational-guidelines.md
+++ b/zh-cn/application-dev/database/database-relational-guidelines.md
@@ -250,7 +250,7 @@
     ```js
     function storeObserver(devices) {
         for (let i = 0; i < devices.length; i++) {
-            console.log('device=' + device[i] + ' data changed')
+            console.log('device=' + devices[i] + ' data changed')
         }
     }
     try {