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Original Description

Description:

DOCS-11933 deals with the documentation changes required by this work.

Engineering Ticket Description:

New format unique indexes would be initially gated by a variable. Start using FCV to enable or disable new format unique indexes:

• Plug-in new format indexes into upgrade/downgrade infratructure.
• Setting FCV=4.2 will cause all exisinting unique indexes to be updated to new format. The content of indexes will not change. New entries will be in new format.
• With FCV=4.0, existing new format index will remain in this format. Any new unique indexes will be created in old V2 format.
• Enhance multiVersion test for collectionsPendingDrop.

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Description

Scope of changes (files that need work and how much)

4.2-compat
4.2-downgrade
unique-index

Impact to other docs outside of this product

MVP (work and date?)

Resources (e.g. Scope Docs, Invision)