Store Parent as Topic Reference?

[JeremyCaney]

A parent is, fundamentally, a topic reference, but it is currently stored on the [dbo].[Topics] table, and not accessible via Topic.References.

Storing it as a topic reference would be more consistent with other topic references and offer better referential integrity, but it would also introduce some specific challenges.

Challenges

• Topic references are versioned, but we don't want a rollback to revert the location in the topic graph. As such, the Parent reference would need to be excluded from a Rollback().
• May need to reintroduce a TopicIndex to combine the latest ParentId with [dbo].[Topics] data. Or could Parent just be assembled just like other topic references?