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https://issues.apache.org/jira/browse/CASSANDRA-8502?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14511355#comment-14511355
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Sylvain Lebresne commented on CASSANDRA-8502:
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Apologies for coming back on this rather late.
I'm +1 on the last version with the following nits.
bq. I feel like this is worthwhile, because without it, all of the slices will
be recreated multiple times for every page on a wide partition. This gets
pretty expensive when you have a lot of slices (for example, with an IN on the
clustering column).
Thing is, paging is stateless. The slices will be recreated multiple times if
the start or end key happens to cover multiple pages with or without this
change because the pages may not even be handled by the same node. The only
case where we do page in a stateful way is for {{SELECT COUNT}}, but I'm not
sure how useful a {{COUNT}} with {{IN}} on the clustering columns is. That's
what bothers me, it's only useful in a very precise case and I fear this will
be more confusing code-wise than anything. But anyway, the new version is
simple enough that I won't fight further if you like it.
bq. I've added one, but basically the reason is that we don't want to record a
static column as the last-seen cell in reversed paged queries.
Saying why using static columns as a start break things doesn't explain why
that is, so I'd to the comment hat the underlying problem is that we query
static columns no matter what the actual filter is, and thus static columns are
not a good indicator of where we are of paging within a partition.
> Static columns returning null for pages after first
> ---------------------------------------------------
>
> Key: CASSANDRA-8502
> URL: https://issues.apache.org/jira/browse/CASSANDRA-8502
> Project: Cassandra
> Issue Type: Bug
> Components: Core
> Reporter: Flavien Charlon
> Assignee: Tyler Hobbs
> Fix For: 2.0.15
>
> Attachments: 8502-2.0.txt, null-static-column.txt
>
>
> When paging is used for a query containing a static column, the first page
> contains the right value for the static column, but subsequent pages have
> null null for the static column instead of the expected value.
> Repro steps:
> - Create a table with a static column
> - Create a partition with 500 cells
> - Using cqlsh, query that partition
> Actual result:
> - You will see that first, the static column appears as expected, but if you
> press a key after "---MORE---", the static columns will appear as null.
> See the attached file for a repro of the output.
> I am using a single node cluster.
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