In WebSphere Message Broker there are two uses for databases: broker databases, which are used to store internal data about the broker, and user databases, which contain your business data. You must create and configure the broker database before you can create any brokers. If you have any user databases you must also configure them before you can use them with WebSphere Message Broker.
A broker stores configuration and control information in its database. You must create the broker database before you can create the broker because when the broker is created, the broker's tables are automatically created in the specified broker database. You can create a database for each broker, or you can use one database for multiple brokers if the platforms are compatible.
If you create a broker on Linux or UNIX, depending on your operating system, you can create the broker database in DB2, Oracle, or Sybase. On Windows, you can create the broker database in DB2, Oracle, Sybase, SQL Server, or Derby. See Supported databases to check which databases are supported on your operating system.
If you create a 64-bit execution group in the broker, the broker database must be a 64-bit database instance.
There is no fixed size requirement for the broker database; the size required depends on the complexity of your message flows and message sets. If you develop message flows that support many publishers or subscribers, you might need to increase your initial sizings.
When you have created a broker database, you must enable a connection from the broker to the database. On all platforms the broker connects to databases using ODBC. For 32-bit brokers (Windows and z/OS), you must always enable a 32-bit ODBC connection. For 64-bit brokers (all other platforms), you must always enable a 64-bit ODBC connection.
For more information about enabling 32-bit and 64-bit connections to the broker database see Broker database connections
User databases are the databases in which you store the business data that will be processed by message flow applications. You can create user databases using any of the database managers that you can use for broker databases. Additional local and remote database managers are also supported; for example, Informix can be used for user databases even though it is not supported for broker databases, while SQL Server running on Windows can be accessed from Linux and UNIX systems. For more information, see Supported databases and Database locations.
You must enable connections to the user databases so that the broker can access the databases on behalf of its deployed message flows. You must enable 32-bit or 64-bit ODBC connections to the user databases depending on whether the message flows that access the user databases are deployed to 32-bit or 64-bit execution groups and whether the message flow transactions are globally coordinated by a 32-bit or 64-bit queue manager.
For information about 32-bit and 64-bit connections to user databases see User database connections.
On Windows or Linux (x86 platform), if you use the Default Configuration wizard to create the Default Configuration, the wizard automatically creates a broker database for the broker. On Linux, the wizard creates the broker database using DB2; on Windows, if DB2 is not installed, the wizard uses the Derby database manager by default, although you can choose to use DB2 if it is installed.