MySQL is a commonly used RDS with a JDBC driver and it is available as a cloud database through AWS for easy setup and maintenance. We will show you how to configure MySQL and RisingWave to create a MySQL sink. The configurations for RisingWave when connecting to any JDBC-available database will be the same.
The supported MySQL versions are 5.7 and 8.0.x

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Set up a MySQL database

Before using the native MySQL CDC connector in RisingWave, you need to complete several configurations on MySQL.

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Set up a MySQL RDS instance on AWS

  1. Log in to the AWS console. Search “RDS” in services and select the RDS panel.
  1. Create a database with MySQL as the Engine type. We recommend setting up a username and password or using other security options.
  1. When the new instance becomes available, click on its panel.
  1. From the Connectivity panel, we can find the endpoint and connection port information.

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Connect to the RDS instance from MySQL

Now we can connect to the RDS instance. Make sure you have installed MySQL on your local machine, and start a MySQL prompt. Fill in the endpoint, the port, and login credentials in the connection parameters.
mysql -h rw-to-mysql.xxxxxx.us-east-1.rds.amazonaws.com -P 3306 -u <username> -p <password>
For more login options, refer to the RDS connection guide.

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Set up a destination table

Use the following query to set up a database and a table in the RDS instance.
CREATE TABLE test_db.personnel (
 id integer,
 name varchar(200),
 PRIMARY KEY (id)
);
If the creation is successful, expect a returned message.
Query OK, 0 rows affected (0.10 sec)

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Set up RisingWave

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Install and launch RisingWave

To install and start RisingWave locally, see the Get started guide. We recommend running RisingWave locally for testing purposes.

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Notes about running RisingWave from binaries

If you are running RisingWave locally from binaries and intend to use the native CDC source connectors or the JDBC sink connector, make sure you have JDK 11 or later versions installed in your environment.

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Create a sink

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Syntax

CREATE SINK [ IF NOT EXISTS ] sink_name
[FROM sink_from | AS select_query]
WITH (
   connector='jdbc',
   field_name = 'field', ...
);

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Parameters

Parameter or clauseDescription
sink_nameName of the sink to be created.
sink_fromA clause that specifies the direct source from which data will be output. sink_from can be a materialized view or a table. Either this clause or a SELECT query must be specified.
AS select_queryA SELECT query that specifies the data to be output to the sink. Either this query or a FROM clause must be specified. See SELECT for the syntax and examples of the SELECT command.
connectorSink connector type must be jdbc for MySQL sink.
jdbc.urlRequired. The JDBC URL of the destination database necessary for the driver to recognize and connect to the database.
userThe user name for the database connection.
passwordThe password for the database connection.
jdbc.query.timeoutSpecifies the timeout for the operations to downstream. If not set, the default is 60s.
jdbc.auto.commitControls whether to automatically commit transactions for JDBC sink. If not set, the default is false.
table.nameRequired. The table in the destination database you want to sink to.
typeData format. Allowed formats:
  • append-only: Output data with insert operations.
  • upsert: Output data as a changelog stream.
primary_keyRequired if type is upsert. The primary key of the downstream table.

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Sink data from RisingWave to MySQL

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Create a table and sink

To sink to MySQL, make sure that RisingWave table and the MySQL table share the same table schema. Use the following queries in RisingWave to create a table and sink. The jdbc.url must be accurate. The format varies slightly depending on if you are using AWS RDS MySQL or a self-hosted version of MySQL. If your MySQL is self-hosted, the jdbc.url would have the following format: jdbc:mysql://127.0.0.1:3306/testdb?user=<username>&password=<password>. 
CREATE TABLE personnel (
 id integer,
 name varchar,
);

CREATE SINK s_mysql FROM personnel WITH (
 connector='jdbc',
 jdbc.url='jdbc:mysql://<aws_rds_endpoint>:<port>/test_db',
 user='<username>',
 password='<password>',
 table.name='personnel',
 type = 'upsert',
 primary_key = 'id'
);

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Update the table

Insert some data with the following query. Remember to use the FLUSH command to commit the update. 
INSERT INTO personnel VALUES (1, 'Alice'), (2, 'Bob');

FLUSH;

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Verify the sink connection

The changes will then be synced to MySQL. To verify the update, connect to MySQL and query the table. The changes you made to the table should be reflected. 
SELECT * FROM personnel;

+------+-------+
| id   | name  |
+------+-------+
|    1 | Alice |
+------+-------+
|    2 | Bob   |
+------+-------+

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Data type mapping

For the MySQL data type mapping table, see the Data type mapping table under the Ingest data from MySQL CDC topic. Additional notes regarding sinking data to MySQL:
  • Array data types in RisingWave when sinked to MySQL will be converted to a string. Only one-dimensional arrays can be sinked to MySQL. For instance, ARRAY['Value 1', 'Value 2'] when sinked to MySQL will be converted to the string Value 1, Value 2.
  • For array type, we only support smallint, integer, bigint, real, double precision, and varchar type now.
  • It’s better to set connectionTimeZone=UTC in jdbc.url to get the correct timestamptz type data. For more details, see MySQL’s documentation.