These are the steps to configure MySQL Data Source in IBM WebSphere:
1. Create JAAS (J2C authentication data) Credential
2. Create MySQL JDBC Provider
3. Create MySQL Data Source

Let’s start to proceed with the detailed steps:

1. Create JAAS Credential
Go to this screen:

Security > Global Security > Authentication > J2C authentication data

Create new authentication data by filling up the username and password. You can give this authentication data a name to use later when connecting data source to database.

2. Create MySQL JDBC Provider
Go to this screen:

Resources > JDBC > JDBC providers

Select the in which scope you want to configure this JDBC Provider, and click New....

Database type: User-defined
Implementation class name: com.mysql.jdbc.jdbc2.optional.MysqlConnectionPoolDataSource
Name: MySQL JDBC Provider
Class path: D:\Java\mysql-connector-java-5.1.33\mysql-connector-java-5.1.33-bin.jar
Check "Isolate this resource provider"

Save the configuration to master configuration.

3. Create MySQL Data Source

Resources > JDBC > Data sources

Select the in which scope you want to configure this Data source, and click New....

Data source name: MySQL Data Source
JNDI Name: jdbc/MySQLDataSource
Select an existing JDBC Provider: MySQL JDBC Provider
Data store helper class name: com.ibm.websphere.rsadapter.ConnectJDBCDataStoreHelper
Keep "Use this data source in container managed persistence (CMP)" checked
Component-managed authentication alias: [Select authentication data name created through step No. 1]
Mapping-configuration alias: (none)
Container-managed authentication alias: [Select authentication data name created through step No. 1]

Save the configuration to master configuration.
Click on the data source name. In Additional Properties click Custom properties.
Search for these entries and set the string value by clicking on each entries, and fill the value in the Value field.

serverName: localhost
portNumber: 3306
databaseName: [database name]

Verifying Data Source

You can back to Resources > JDBC > Data sources to test the configuration by selecting the data source and click on the Test connection button.