Oracle7 Server Distributed Systems Volume II: Replicated Data
Declaring a Conflict Resolution Method
As you create a replicated table, you should designate one or more methods to resolve any potential conflicts.
To declare a conflict resolution method, first complete the planning phase:
- Analyze your data to determine which column groups are appropriate, and which conflict resolution methods are appropriate for each column group.
- Create columns, such as timestamp, and maintenance triggers as needed by the methods that you select.
- If desired, define notification packages.
- create a table to hold conflict notification information at each master site
- create the PL/SQL procedure to record conflict notification in the table
- add user defined conflict resolutions to the package or add routines to automate e-mail notification (optional)
- If any column groups in any table will use site priority or priority groups for conflict resolution, define the priority levels for each site or value.
After planning, call the appropriate procedures in the DBMS_REPCAT package:
1. If you are adding conflict resolution to an existing replicated environment, you must first suspend all replication activity, as described ![[*]](jump.gif)
If you are creating a new replication group, follow the instructions for creating a replication group and creating replicated objects beginning, .
2. Define the column groups for each table.
3. Distribute the conflict notification package and notification log table to the remote sites by registering it as a replicated object in the same object groups as the table monitored for conflicts (optional)
Note: Do not use this option if each remote site is to customize the notification package.
4. Assign one or more conflict resolution methods for each column group.
5. Generate support for the replicated tables, as described .
Caution: Do not generate replication support for the conflict notification table. The data in this table must remain specific to its site.
6. Create a timestamp and maintenance trigger (if needed).
7. Resume replication activity, as described .
Suggestion: To define the conflict notification routine(s) for your site, use the example . Modify and/or expand upon the example with your own conflict resolution routines.