On Mon, 30 Jan 2012 11:14:37 -0600
Bryce Allen <bal...@ci.uchicago.edu> wrote:
> With RP, the idea is to query many versions in ListVersionIndex
> starting at the desired version going backward, hoping that it will
> hit a compact version. We could also maintain a separate
> CompactVersion index, and accept another query.
Actually a better way to handle this is to store the latest compacted
version with each delta version in the index. When doing compaction, all
the deltas between it and the next compaction (or end) are updated to
point at the new compaction. E.g.:

ts0:  20;20 <- compacted version
ts1:  21;20
ts2:  22;20
...
ts9:  29;20
ts10: 30;20
ts11: 31;20

compaction is done on version 30:

...
ts9:  29;20
ts10: 30;30 <- new compacted version
ts11: 31;30

Perhaps "compaction" is a bad term because it already has meaning in
Cassandra, but I can't think of a better name at the moment.

-Bryce

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