1# Data Management - Distributed Relational Database 2 3### Introduction 4 5This sample shows how to add, delete, modify, query, and synchronize data in the distributed relational database with extended TypeScript (eTS). 6 7### Usage 8 91. After starting the app, touch **+** to add a contact. 10 112. Touch a contact. On the edit page displayed, you can modify the contact information. 12 133. Touch and hold a contact. The **Select All**, **Cancel**, **Delete**, and **Quit** buttons are displayed at the bottom of the screen. You can touch **Quit** to quit the current page. 14 154. Touch the **More** button in the upper right corner, touch **Connect device**, and select the device with data to be synchronized. After the connection is set up, data is synchronized to the connected device. 16 175. Touch the **More** button in the upper right corner and touch **Settings**. On the page displayed, you can set the data synchronization mode, which can be **Automatic synchronization** or **Manual synchronization**. 18 19### Constraints 20 21- Two networked devices are required to test the data synchronization function. 22 23- This sample can run only on standard-system devices, and API version 8 or later are supported. 24 25- This sample requires DevEco Studio 3.0 Beta4 (Build Version: 3.0.0.992, built on July 14, 2022) to compile and run. 26