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https://issues.apache.org/jira/browse/CASSANDRA-7859?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14200482#comment-14200482
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Tyler Hobbs commented on CASSANDRA-7859:
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bq. To reiter, collection values are sorted (even when used as cell values),
and so it felt fishy to me to consider that changing to a type that change the
internal sorting of those values is "compatible"
Right, I agree with that, and the current patch doesn't change that. I think
an example will clarify this. Take the type {{frozen<list<int>>}}. If you use
that type for a clustering column, then entire lists will be compared (is [1,
2, 3] > [2, 3, 4]? etc) to sort the cells. In this case, the sorting order of
{{int}} must be maintained when you alter the type. However, if you use
{{frozen<list<int>>}} for a cell value, that sorting order no longer matters.
It would be safe to alter it to {{frozen<list<bytes>>}}.
That does *not* apply to sets, because the items within a set should be sorted.
It also does not apply to map *keys*, but map *values* can be treated like
list values.
Does that clarify things? I was a little tired when I tried to explain it last
night.
bq. Maybe we should just remove the comment in that case.
Yup, already removed it in the last commit.
What do you think about my comment on 8264 and getRequestedColumns?
> Extend freezing to collections
> ------------------------------
>
> Key: CASSANDRA-7859
> URL: https://issues.apache.org/jira/browse/CASSANDRA-7859
> Project: Cassandra
> Issue Type: Improvement
> Reporter: Sylvain Lebresne
> Assignee: Tyler Hobbs
> Labels: cql
> Fix For: 2.1.2
>
> Attachments: 7859-v1.txt
>
>
> This is the follow-up to CASSANDRA-7857, to extend {{frozen}} to collections.
> This will allow things like {{map<text, frozen<map<int, int>>>}} for
> instance, as well as allowing {{frozen}} collections in PK columns.
> Additionally (and that's alsmot a separate ticket but I figured we can start
> discussing it here), we could decide that tuple is a frozen type by default.
> This means that we would allow {{tuple<int, text>}} without needing to add
> {{frozen}}, but we would require {{frozen}} for complex type inside tuple, so
> {{tuple<int, list<text>>}} would be rejected, but not {{tuple<int,
> frozen<list<text>>>}}.
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