Table Name	Reason for Exclusion	Cascade Delete
AttachedContentDocument	Salesforce limitation - not queryable	True
CombinedAttachment	Salesforce limitation - not queryable	True
ContentVersion	-	False
EmailMessage	-	False
EmailStatus	-	False
PartnerNetworkRecordConnection	-	True
TaskFeed	Subset of FeedItem	True

When the archive job purges task records, records from the excluded child tables that have cascade delete set to true will also be purged by Salesforce. Some tables are excluded from the entity because they are a subset of another table. Even though data from these tables is purged by Salesforce, there is no data loss on the subset tables because the same data is available in the superset table, which is part of the Task entity.

Note that some tables are excluded from the entity because they are not available unless features like tag, shared activites, and network communities are enabled.