Migrate data from a MySQL database in OceanBase Database to a MySQL database using ChunJun|V4.3.1| docs|Distributed Database

Migrate data from a MySQL database in OceanBase Database to a MySQL database using ChunJun

Last Updated：2025-12-04 07:48:15 Updated

ChunJun (formerly known as FlinkX) is a stable, user-friendly, and efficient data integration framework that supports batch and stream processing. Currently, it uses the real-time computing engine Flink to synchronize data and perform computations among various heterogeneous data sources. OceanBase Binlog Service (OceanBase Binlog Service, shortly Binlog Service) collects transaction logs from OceanBase Database and converts them into MySQL Binlog. It is mainly used in real-time data subscription scenarios.

ChunJun Connector for OceanBase CDC integrates oblogclient internally to connect to the Binlog Service, retrieve relevant log data, and migrate incremental data from OceanBase Database.

This topic will guide you through the process of using ChunJun in Local mode to migrate data from a MySQL database in OceanBase Database to a MySQL database.

Scenario description

Migrate data from the test_tbl1 table in OceanBase Database to the tbl1 table in MySQL Database. The databases are configured as follows:

OceanBase Database (source database)	Example value
Cluster name	test4000
Host address	10.10.10.2
Port number	2881
IP address of the Binlog service	10.10.10.3
Port number of the Binlog service	2983
Name of the business tenant (MySQL mode)	mysql001
Username	root
Password	******
Schema database name	test_data
Table name	test_tbl1

MySQL Database (target database)	Example value
Host address	10.10.10.1
Port number	3306
Username	root
Password	******
Schema database name	test_ob_to_mysql
Table name	tbl1

Prerequisites

JDK 1.8 has been installed, and the JAVA_HOME environment variable has been configured.
The Binlog service has been installed and deployed. For more information, see Create a Binlog cluster.

Procedure

Step 1: Prepare the ChunJun environment

Download and decompress the ChunJun package.

Download chunjun-dist.tar.gz.

wget https://github.com/DTStack/chunjun/releases/download/v1.12.6/chunjun-dist.tar.gz

Decompress the package to the /chunjun_Home/chunjun directory.

mkdir /ChunJun_Home/chunjun && tar zxvf chunjun-dist.tar.gz -C /ChunJun_Home/chunjun

Configure the ChunJun environment variables.

export ChunJun_HOME=/ChunJun_Home/chunjun-dist

Step 2: Configure the json file

Configure the json file to migrate the data from the test_tbl1 table in OceanBase Database to the tbl1 table in MySQL Database based on the environment information.

Here is an example:

[root@xxx /]
$cd /ChunJun_Home/chunjun-dist/chunjun-examples/json

[root@xxx /ChunJun_Home/chunjun-dist/chunjun-examples/json]
$mkdir test_data

[root@xxx /ChunJun_Home/chunjun-dist/chunjun-examples/json]
$cd mkdir test_data

[root@xxx /ChunJun_Home/chunjun-dist/chunjun-examples/json/test_data]
$vi test_ob_to_mysql.json

{
  "job": {
    "setting": {
      "errorLimit": {
        "record": 0,
        "percentage": 0.02},
      "speed": {"bytes": 0,
      "channel": 1}
    },
    "content": [
      {
        "reader": {
          "name": "oceanbasecdcreader",
          "table": {
            "tableName": "test_tbl1"},
          "parameter": {
            "logProxyHost": "10.10.10.3",
            "logProxyPort": 2983,
            "obReaderConfig": {
              "rsList": "10.10.10.2:2882:2881",
              "username": "root",
              "password": "******"
            },
            "cat": "insert,delete,update",
            "column": [
              "*"
            ]
          }
        },
        "writer": {
          "name": "mysqlwriter",
          "parameter": {
            "column": [
              "*"
            ],
            "connection": [
              {
                "jdbcUrl": "jdbc:mysql://10.10.10.1:3306/test_ob_to_mysql",
                "table": [
                  "tbl1"
                ]
              }
            ],
            "username": "root",
            "password": "******"
          }
        }
      }
    ]
  }
}

Step 3: Run the json configuration file

Start a JVM process to run the ChunJun task.

Go to the /ChunJun_Home/chunjun-dist directory and run the following command:

[root@xxx /]
$cd /ChunJun_Home/chunjun-dist

[admin@xxx /ChunJun_Home/chunjun-dist]
$sh bin/chunjun-local.sh -job chunjun-examples/json/test_data/test_ob_to_mysql.json

          #                               #
          #                               #
          #
  #####   ######   #     #  # ####     ####   #     #  # ####
 #        #     #  #     #  ##    #       #   #     #  ##    #
 #        #     #  #     #  #     #       #   #     #  #     #
 #        #     #  #    ##  #     #       #   #    ##  #     #
  #####   #     #   #### #  #     #       #    #### #  #     #
                                          #
                                      ####

Reference site: https://dtstack.github.io/chunjun

chunjun is starting ...
CHUNJUN_HOME is auto set /ChunJun_Home/chunjun-dist/
FLINK_HOME is empty!
HADOOP_HOME is empty!
...
<ellipsis>
...
*********************************************
numWrite                  |  3
last_write_num_0          |  0
conversionErrors          |  0
writeDuration             |  20149
duplicateErrors           |  0
numRead                   |  3
snapshotWrite             |  0
otherErrors               |  0
readDuration              |  95
byteRead                  |  389
last_write_location_0     |  0
byteWrite                 |  389
nullErrors                |  0
nErrors                   |  0
*********************************************

2023-01-06 20:34:47,448 - 50317 INFO  [main] com.dtstack.chunjun.Main:program Flink_Job execution success

Step 4: Incrementally modify data in OceanBase Database

[admin@xxx /home/admin]
$obclient -h10.10.10.2 -P2881 -uroot@mysql001 -p****** -Dtest_data
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Welcome to the OceanBase.  Commands end with ; or \g.
Your OceanBase connection id is 3221709678
Server version: OceanBase 4.0.0.0 (r101000022022120716-0d7927892ad6d830e28437af099f018b0ad9a322) (Built Dec  7 2022 16:22:15)

Copyright (c) 2000, 2018, OceanBase and/or its affiliates. All rights reserved.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

obclient [test_data]> INSERT INTO test_tbl1 VALUES(4,'Macao',853);
Query OK, 1 row affected

Step 5: View the migration results

[admin@xxx /home/admin]
$mysql -h10.10.10.1 -P3306 -uroot -p******
Welcome to the MariaDB monitor.  Commands end with ; or \g.
Your MySQL connection id is 189769
Server version: 5.7.26-log MySQL Community Server (GPL)

<ellipsis>

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

MySQL [(none)]> use test_ob_to_mysql;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Database changed
MySQL [test_ob_to_mysql]> SELECT * FROM tbl1;
+------+-----------+------+
| col1 | col2      | col3 |
+------+-----------+------+
|    1 | China     |   86 |
|    2 | Taiwan    |  886 |
|    3 | Hong Kong |  852 |
|    4 | Macao     |  853 |
+------+-----------+------+
4 rows in set

References

For more information about how to get started with ChunJun, see Quick start.
For more information about the JSON configuration file of the target MySQL database, see MySQL Sink.
For more script examples, see the /chunjun-dist/chunjun-examples folder in the project.