Index migration

Migration is the process by which Content Manager OnDemand moves index data from the database to archive storage. Migration optimizes database storage space while allowing you to maintain index data for a very long time. You typically migrate index data after users no longer need to access the reports, but, for legal or other requirements, you still need to maintain the data for some number of months or years. If a user queries index data that has been migrated, then an administrator must import a copy of the migrated table or tables using the ARSADMIN program. After maintaining the imported index data in the database for the number of days specified in the Keep Imported Migrated Indexes field, Content Manager OnDemand deletes the data from the database.

A table of index data for a Multiple Loads per Database Table application group is eligible for migration when it reaches the Maximum Rows value. For a Single Load per Database Table application group, each time that you load data into the application group, Content Manager OnDemand creates a new table.

You should migrate index data only after users no longer need to access the data. If a user needs to access data in migrated tables, then the process of importing the data into the database requires administrator intervention, and usually results in a significant delay in completing the query. Additional space is required in the database and in temporary storage areas to import data.

To enable migration of index data, you must define a storage set that identifies a storage node that is maintained by the archive storage manager and update the System Migration application group to use the storage set.

Note: You should not use index migration on an IBM® i server.