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https://issues.apache.org/jira/browse/CASSANDRA-9779?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15729356#comment-15729356
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Jeff Jirsa commented on CASSANDRA-9779:
---------------------------------------
Old stale ticket, but fwiw re: [~slebresne] 's comment on dtcs (/twcs) -
This ticket would enable modifying
{{CompactionController.getFullyExpiredSSTables()}} to be more closely aligned
with what people expect it to do, eliminating the need for
{{sstableexpiredblockers}} and the like. Performance wise, its probably a minor
gain, but operationally it's probably a big net gain in terms of least-surprise.
> Append-only optimization
> ------------------------
>
> Key: CASSANDRA-9779
> URL: https://issues.apache.org/jira/browse/CASSANDRA-9779
> Project: Cassandra
> Issue Type: New Feature
> Components: CQL
> Reporter: Jonathan Ellis
> Fix For: 3.x
>
>
> Many common workloads are append-only: that is, they insert new rows but do
> not update existing ones. However, Cassandra has no way to infer this and so
> it must treat all tables as if they may experience updates in the future.
> If we added syntax to tell Cassandra about this ({{WITH INSERTS ONLY}} for
> instance) then we could do a number of optimizations:
> - Compaction would only need to worry about defragmenting partitions, not
> rows. We could default to DTCS or similar.
> - CollationController could stop scanning sstables as soon as it finds a
> matching row
> - Most importantly, materialized views wouldn't need to worry about deleting
> prior values, which would eliminate the majority of the MV overhead
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