Oracle to DB2 UDB Conversion Guide2003

6.2 Time planning

After testing the data movement and choosing the proper tool and strategy, you have to create a detailed time plan with following tasks:

• Depending on the data movement method:

  • Implementing or modifying scripts for data unload and load

  • Learning the use of the chosen data movement tools

• Data unload from Oracle

• Data load to DB2 UDB

• Backup target database

• Test loaded data on completeness and consistency

• Switch of applications including database interfaces

• Fallback process in case of incidents

The most sensitive environment is a production system with a 7x24 hours availability requirement. Figure 6-1 shows you the way how to move the data to the target database in a high availability environment. The dark color represents the new data, the light color represents the converted and moved data. If possible, export the data from a standby database or mirror database to minimize the impact on the production environment. You have to do following tasks:

1. Create scripts that export all data up to a defined timestamp.

2. Create scripts that export changed data since the last export. This includes new data as well as deleted data.

3. Repeat step 2 as often as when all data is moved to the target database.

4. Define fallback strategy and prepare fallback scripts.

Figure 6-1: Data movement strategy in a high availability environment

When the data is completely moved to the target database, you can switch the application and database. Prepare a well defined rollout process for the applications, and the belonging interfaces to DB2 UDB. Allow time for unplanned incidents.