[Bigdata-developers] fast range counts guarantees

[Jeremy J C. <jj...@sy...>]

I am reading the documentation on fast range counts.

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Fast range counts are exact when running against a BigdataSail on a local journal which has been provisioned without full read/write transactions. When full read/write transactions are enabled, the fast range counts will also report the "delete markers" in the index. In scale-out, the fast range counts are also approximate if the key range spans more than one shard (in which case you are talking about lot of data).
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I am not totally clear what  "provisioned without full read/write transactions”; it seems that in either case, the fast range count will consistently over-estimate, so that a value of 0 always means 0.

Is this correct? (Just the last statement would be helpful: to know if a pattern never matches)

Jeremy