Use a covered index scan in analyze ndv mode when a suitable index exists

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    • Type: Task
    • Resolution: Unresolved
    • Priority: Minor - P4
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    • Affects Version/s: None
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    • Query Optimization
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      The analyze ndv mode always builds HLL statistics via a full collection scan. When a suitable index exists for the requested field, the NDV could even be computed exactly by boundary counting, without HLL. The system could even choose when you ask analyze to calculate NDV / column statistics based on the available indexes whether to use HLL or a covered index scan.

            Assignee:
            Unassigned
            Reporter:
            Max Verbinnen
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              Created:
              Updated: