update format

Signed-off-by: Nwuyongning <wuyongning@huawei.com>

zh-cn/application-dev/database/database-relational-guidelines.md

@@ -317,7 +317,7 @@
     ```js
     let predicate = new data_rdb.RdbPredicates('test')
     predicate.inDevices(['12345678abcde'])
-    let promise = rdbStore.sync(rdb.SyncMode.SYNC_MODE_PUSH, predicate)
+    let promise = rdbStore.sync(data_rdb.SyncMode.SYNC_MODE_PUSH, predicate)
     promise.then((result) => {
         console.log('sync done.')
         for (let i = 0; i < result.length; i++) {
@@ -343,7 +343,7 @@
         }
     }
     try {
-        rdbStore.on('dataChange', rdb.SubscribeType.SUBSCRIBE_TYPE_REMOTE, storeObserver)
+        rdbStore.on('dataChange', data_rdb.SubscribeType.SUBSCRIBE_TYPE_REMOTE, storeObserver)
     } catch (err) {
         console.log('register observer failed')
     }