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https://issues.apache.org/jira/browse/CASSANDRA-7857?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14117682#comment-14117682
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Aleksey Yeschenko commented on CASSANDRA-7857:
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TBH I'm not really okay w/ frozen, or final, or static - because some people
might get wrong ideas about the finality of the values. Namely, that you can
only write them once.
'serialized' or 'packed', on the other hand, are not misguiding, at least when
it comes to the finality of the values. I realize that 'serialized' is a bit
overloaded. In absence of new ideas my vote goes to either 'packed' or
'serialized'.
> Ability to froze UDT
> --------------------
>
> Key: CASSANDRA-7857
> URL: https://issues.apache.org/jira/browse/CASSANDRA-7857
> Project: Cassandra
> Issue Type: Improvement
> Reporter: Sylvain Lebresne
> Assignee: Sylvain Lebresne
> Fix For: 2.1.0
>
> Attachments: 7857-v2.txt, 7857.txt
>
>
> Currently, UDT are serialized into a single value. For 3.0, we want to change
> that somewhat and allow updating individual subfields: CASSANDRA-7423 (and
> ultimately, we'll probably allow querying subpart of UDT to some extend).
> Also for 3.0, we want to allow some nesting of collections (CASSANDRA-7826).
> However, migrating the currently serialized UDT would be challenging. Besides
> that, even with nested collections, we probably won't be able to support
> nesting within map keys and sets without serializing (at the very least, not
> initially). Also, it can be useful in some specific case to have UDT or
> collections for PK columns, even if those are serialized.
> So we need a better way to distinguish when a composite types (collections &
> UDT) are serialized (which imply you can't update subpart of the value, you
> have to rewrite it fully) and when they are not. The suggestion is then to
> introduce a new keyword, {{frozen}}, to indicate that a type is serialized:
> {noformat}
> CREATE TYPE foo (a int, b int);
> CREATE TABLE bar (
> k frozen<foo> PRIMARY KEY,
> m map<frozen<set<int>>, text>
> )
> {noformat}
> A big advantage is that it makes the downside (you can't update the value
> without rewriting it all) clear and upfront.
> Now, as of 2.1, we only support frozen UDT, and so we should make this clear
> by 1) adding the frozen keyword and 2) don't allow use of UDT unless they are
> "frozen" (since that's all we really support). This is what this ticket
> proposes to do. And this should be done in 2.1.0 or this will be a breaking
> change.
> We will have a follow-up ticket that will extend {{frozen}} to collection,
> but this is less urgent since this will be strictly an improvement.
> I'll note that in term of syntax, {{serialized}} was suggested as an
> alternative to {{frozen}}. I personally have a minor preference for
> {{serialized}} but it was argued that it had a "sequential" connotation which
> {{frozen}} don't have. Changing that is still up for discussion, but we need
> to reach a decision quickly.
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