Page History

The Online index rebuild operation is an application that upgrades indexes in the background and converts Indexes from none compression to a page level compression type. This operation updates indexes on the Events table in each of the monitored instance databases to become page compressed type. The operation is performed as an ONLINE operation (only for supported SQLServer versions) keeping the database table(s) available for users. This index upgrade shows considerable performance advantage and optimizes performance when viewing and managing event data.

The following 7 Indexes are included to the Events table of an instance being audited:

• IX_Events_eventId
• IX_Events_eventCategory
• IX_Events_eventType
• IX_Events_databaseId
• IX_Events_appNameId
• IX_Events_hostId
• IX_Events_loginId

The process first creates the non existing 7 indexes mentioned above, after creation it performs the compression on the 7 indexes of the event databases (for each instance added for
auditing).

The index upgrade is skipped if the compression type is already of page type. 

For new instances, it will create the page compressed type indexes by default.

In a few SQL Servers versions (such as the STANDARD edition), the index creation with the ONLINE property is not supported and therefore the operation results in a failure message displayed to the user, instructing to run the application manually without the ONLINE property.

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