Setting up and configuring subscriptions
A subscription is a connection that is required to replicate data between a source datastore and a target datastore. It contains details of the data that is being replicated and how the source data is applied to the target.
Subscriptions use datastores as the source or target of replicated data. You can view the datastores that your subscriptions are using in the Source and Target columns of the Subscriptions view.
Before you can start replicating data, you need to add a subscription. When adding a new subscription, you can organize your subscription into a project and select the datastores you want to use as the source and target of data during replication activities. How you decide to set up the datastores in your subscriptions depends on your replication requirements.
Setting up subscriptions for datastores outside of your organization
You can also add subscriptions that send data to a target datastore that is external to your organization. In order to set up a subscription that sends data to an external target datastore, the receiving organization must have installed Management Console and you must have the necessary authentication and database details to connect to their target datastore.
External source or target datastores are not available in your Access Manager, either because they reside outside of your organization or department, or your system administrator has not given you the permission to access it.
If you have received authorization from the company or organization to which you are replicating data, then you can modify the properties of an external target datastore, including the port number, owner, and password. System and database information about external target datastores is provided by the organization or department that owns that datastore.
You can also copy subscriptions that send data to an external target. This is a timesaving mechanism.
If your organization is at the receiving end of replication activities coordinated with another organization that is outside of your database security policy, then you should see Unknown source datastores in your subscription list. This is because you are receiving replicated data from a source datastore that is outside of your security policy (and, therefore, to which you do not have access to) and the name of the source datastore is not known to you.
Setting properties for a subscription that targets IBM® InfoSphere DataStage
If you create a subscription that uses a CDC Replication Engine for InfoSphere® DataStage® as a target datastore, you can modify the following subscription properties:
- Batch size thresholds
- InfoSphere DataStage uses jobs to process batches of data. When balancing the need to get data applied to the target quickly against the need to minimize resource utilization, you can set the batch size threshold property to run jobs less frequently and process larger amounts of data.
- Large object truncation size for character and binary data
- The truncation point affects the fixed record length used by an InfoSphere DataStage job that processes the changed data. You should set this property to as small a size as possible while still retaining enough of the data from the large columns to meet your business needs.