Required database, user accounts, and schemas

Configuring an Oracle database

When you configure CDC Replication, you are prompted for the name of the Oracle database to which you want CDC Replication to replicate data. Before installing CDC Replication, ensure that this Oracle database exists and that you have created and set up a database user that has access to it. The CDC Replication Engine for Oracle XStream supports mapping tables that reside in multiple schemas within the same database. Ensure that Oracle XStream is enabled through the enable_goldengate_replication parameter.

Some of the Oracle XStream configuration must be prepared in advance, prior to configuring a CDC Replication instance.

Enable enable_goldengate_replication

You need to set the enable_goldengate_replication system parameter on your source database to enable XStream replication capability in Oracle. You could use the following statement:

ALTER SYSTEM SET enable_goldengate_replication=TRUE SCOPE=BOTH

All instances in Oracle RAC must have the same setting. Refer to the Oracle documentation for further understanding of the impact of enabling this parameter on your database.

Setting up a UNIX user account

When you are installing CDC Replication on a UNIX machine, you must set up a new UNIX account, or decide on an existing UNIX account that you will use to install, configure, or upgrade CDC Replication. You can install CDC Replication in the directory of your choice, however, it must be owned by the UNIX account.

Setting up a Windows user account

When you are installing CDC Replication on a Windows machine, you must set up a new, or decide on an existing Windows account that you will use to install, configure, or upgrade CDC Replication. The Windows user must have administrator authority and network authority.

Setting up an Oracle user account

Create a user account for the Oracle database. When you configure a new instance of CDC Replication, you are prompted for the name of the Oracle database that you want CDC Replication to connect to, as well as for the user name and password of the Oracle user that has access to this database. Credentials are case sensitive.

Reviewing required privileges for Oracle users

Before configuring CDC Replication, you should review the list of privileges required by Oracle users. You are required to grant these privileges to users by running SQL scripts which are located in the/samples directory of your installation folder. You must grant privileges after installing CDC Replication so that you can access the necessary SQL script.

After you install the product, the /samples folder will contain sample scripts that can help provide appropriate privileges to the Oracle database user as well as the Log Processing Database user. Review the file createuser-ora-xstream.sql in the samples folder after installation for more details.

Configuring the log processing database

When you configure CDC Replication, you are prompted for the name of the Oracle log processing database that you want CDC Replication to use. This database serves an XStream outbound database to which CDC Replication connects and attaches to process Logical Change Records that are supplied by the Oracle XStream API. For local Oracle XStream capture and outbound server, this is the same database as before. For pluggable databases, the log processing database is the root container database. For downstream capture, the log processing database is the downstream database. The log processing database also requires enable_goldengate_replication.

Configuring a downstream log processing database

A number of steps are required to configure either real-time downstream capture or archive-log downstream capture. Review the Oracle XStream documentation to configure database links and log file transfer.

Setting up Oracle XStream user account

Most work in CDC Replication is done using the Oracle user account. When CDC Replication needs to interact with Oracle XStream, it uses the Oracle XStream account. An Oracle XStream account needs sufficient privileges to comply with Oracle XStream user requirements. In a pluggable database environment, the Oracle user account has all the granted access to the pluggable database when replication is configured for a pluggable database, whereas the XStream user account has to be defined in the root container database as per Oracle XStream requirements. All Oracle XStream related components are defined and managed in the root container database in this case. You could use DBMS_XSTREAM_AUTH.GRANT_ADMIN_PRIVILEGE to grant XStream user account privileges. Oracle XStream outbound database credentials are case sensitive. For more information review the Oracle documentation.

Configuring an Oracle schema

Create a schema or choose an existing schema for your database metadata tables. You will have to specify this schema when you configure CDC Replication.