Overview

Adabas Audit Data Retrieval supports different index types:

• Local Indexes

  A local index is list-based. Each local index generation contains values of one list generation.

  Local indexes are used to search within a specific list. Adabas Audit Data Retrieval supports two types of local indexes:

  • A primary index stores the indexed values in alphabetical order. This is the normal case.
  • A secondary index stores indexed values ordered by page numbers (item numbers).
• Global Indexes

  A global index is a cross-list index which contains the values of multiple index generations.

  Global indexes are used to search for lists via indexed contents.

Updating the global index

Local indexes are created as lists are read in. Global indexes are created or updated by the batch utility B97GLOBL.

The following actions are carried out during each B97GLOBL run:

• The hit-lists of the newly created primary indexes are merged with the existing hit-lists of the global index.

  Doublets are deleted from the hit-lists prior to the merge because storing a single occurrence of each hit per list is enough for finding the list.

• The hits of lists that have expired are deleted from the global index.

Global index requires a local index

Local primary indexes must exist in order to create a global index.

Both index types are used for the search of hits in a list:

• The list is found via the global index(es).
• The hits in the list are found via the local index(es).

Online/Offline

Global indexes always remain online.

Primary indexes must remain online at least until B97GLOBL has merged them into the corresponding global indexes. The insertion of primary indexes that are offline is not supported.

After a primary index has been inserted successfully by the batch utility B97GLOBL, the primary index is no longer required for updating the global index and can be online or offline.