ReportServer uses Hibernate Envers (https://hibernate.org/orm/envers/) as an archiving / versioning solution for entity classes. This might result in an unexpected and unwanted growth of size of the ReportServer repository database.

A new revision is created on every single entity change, so the archive tables grow with each entity modification. Thus, these tables get larger and larger, making your DB occupy a large amount of space after some time. If you don’t need the archive tables, you can easily turn this behaviour off.

For each table in the ReportServer repository there is a shadow table which has the same as the original tables plus the suffix _A. All entity versions can be found in the these tables. The “_A” suffix stands for “archive” or “audit”. So, e.g., your User’s revisions are found in the RS_USER_A archive table, since the respective actual entity versions are located in the RS_USER table.

To stop this behaviour in your ReportServer installation, open your persistence.xml and locate the section containing the string <!– Envers –>.
Then add the following:

<property name="hibernate.integration.envers.enabled" value="false"/>

The result would be similar to:

<!-- Envers -->
<property name="org.hibernate.envers.audit_table_suffix" value="_A"/>
<property name="org.hibernate.envers.audit_table_prefix" value=""/>
<property name="hibernate.integration.envers.enabled" value="false"/>

After a ReportServer restart, you can make sure that the archive tables are switched off by opening a ReportServer terminal session and typing a rev command for a given entity, as in this example:

If you get the message “Service is not yet initialized”, the archive tables are correctly turned off.

Once your archive tables are switched off, you can modify your “_A” tables: you can either leave them as they are or delete the entries.

Attention:
Once the archive tables are switched off, they cannot be switched on again unproblematically.
Pls. do not confuse the archive tables with the audit log ReportServer maintains in the RS_AUDIT_* tables. These are not impacted by the operations described above.