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https://issues.apache.org/jira/browse/CASSANDRA-8483?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14246722#comment-14246722
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Sylvain Lebresne commented on CASSANDRA-8483:
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Not entirely convinced we should start by the native protocol. There is a fair
amount of obstacles to actually stream results internally: CASSANDRA-8100 is a
first one but more generally we'd probably need deeper change to the inter-node
protocol to actually stream results, digest queries is another part that is not
trivially amenable to streaming in it's current state, etc.... All of this can
of course be changed, but I wonder how quickly we can get there in practice, or
even if the effort is really worth the trouble (not saying it's not, saying
it's a question worth asking). In that context, starting by complicating the
native protocol (making the life of all drivers author harder) doesn't
necessarilly feel to me like the good first step, and I'd rather wait until
we're almost there internally (which will definitively not be 3.0) before
considering this.
> Support streaming results
> -------------------------
>
> Key: CASSANDRA-8483
> URL: https://issues.apache.org/jira/browse/CASSANDRA-8483
> Project: Cassandra
> Issue Type: Sub-task
> Components: Core
> Reporter: Benedict
> Fix For: 3.0
>
>
> Currently we stream the number of rows back to the client before serializing,
> which means we need to know how many there are before doing so, which means
> materializing the entire resultset. We currently get around this with paging
> which attempts to restrict the amount of materialization done in any step,
> but supporting streaming entire result sets in one native transport "action"
> without materializing them all upfront would remove the need for paging in
> many cases, and would permit resultsets to be streamed _with isolation_,
> which most users probably don't realise is broken by paging.
> We can't use this change yet, but the sooner support for this is introduced
> to the protocol, the more likely it is clients will be able to make use of
> streaming reads once we're actually able to deliver them.
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