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1. Supporting SQL and non-SQL indexes on the same field - they must work equally.
2. Rebuild, clear, defragmentation tasks, control.sh, system views, IndexRowCache, security checks, etc(?) for non-SQL indexes - all of the tooling should work correctly with non-SQL indexes.
3. Need support for tracking index queries (security checks, tracing, query views).
4. Transactional support for "update for select" should be discovered.
5. There can be performance issues with IndexFieldsOnly queries due to reflection, or wrong inlining.

Jira Tickets