Pruning of the control tables

In the previous section, it was discussed how the control tables were populated. This section discusses how they are pruned. The control tables can be pruned automatically by Q Capture and Q Apply (and the Replication Alert Monitor) or can be pruned manually.

Let's first look at the tables that need to be pruned:

• Q Capture: IBMQREP_CAPMON, IBMQREP_CAPQMON, IBMQREP_CAPTRACE, and IBMQREP_SIGNAL.

• Q Apply: IBMQREP_APPLYMON and IBMQREP_APPLYTRACE.

• The Replication Alert Monitor: IBMSNAP_ALERTS and IBMSNAP_MONTRACE.

When it comes to dealing with data in these control tables, we have two questions:

• How long should the data stay in the tables?

• Once we have decided that data should be deleted, when is this done?

There are two parameters which manage the answer to both of these questions:

1. 1. For the xxxMON and CAPQMON tables the answer to the first question is provided by the MONITOR_LIMIT parameter, which determines how long data should be kept in the tables.

2. 2. The second...