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https://issues.apache.org/jira/browse/CASSANDRA-4284?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13283746#comment-13283746
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Jonathan Ellis commented on CASSANDRA-4284:
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bq. it would make more sense that when inserting a date, we actually pick a 
uuid with the corresponding timestamp but with the rest of the UUID being random

+1

bq. We could extends the date syntax to allow it to represent uniquely a type 1 
UUID. Typically, we could allow something like: '2012-06-06 12:03:00+0000 
%a2fc07', where the part after the '%' character would be hexadecimal for the 
non-timestamp part of the UUID

+0, sounds messy wrt the general to/from string api in AbstractType.
                
> Improve timeuuid <-> date relationship
> --------------------------------------
>
>                 Key: CASSANDRA-4284
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-4284
>             Project: Cassandra
>          Issue Type: Improvement
>          Components: API
>    Affects Versions: 1.1.0
>            Reporter: Sylvain Lebresne
>            Assignee: Sylvain Lebresne
>            Priority: Minor
>              Labels: cql3
>             Fix For: 1.2
>
>
> We added timeuuid to CQL3, whose purpose is to provide a collision-free 
> timestamp basically and as a convenience, such timeuuid can be inputed as as 
> date.
> However, two things seems non-optimal to me:
> * When one insert a timeuuid using a date format, we always pick *the* UUID 
> corresponding to this date with every other part of the UUID to 0. This kind 
> of defeat the purpose of collision-free timestamp and thus greatly limit the 
> usefulness of the date syntax.
> * When cqlsh print timeuuid, it print them as date. But as thus, there is 
> some information lost which can be problematic (you can't update a specific 
> column based on that return). In a way, this is a cqlsh limitation, since 
> cassandra return the UUID bytes. Yet, it also emphasis somehow that from the 
> point of using them, timeuuid are more UUID than really time.
> For the first point, it would make more sense that when inserting a date, we 
> actually pick a uuid with the corresponding timestamp *but* with the rest of 
> the UUID being random. It's not completely that simple because we don't want 
> that randomness when the date are used in a select query, but that's roughtly 
> the same problem than CASSANDRA-4283 (and we can thus use the same solution).
> The second point gives an idea. We could extends the date syntax to allow it 
> to represent uniquely a type 1 UUID. Typically, we could allow something 
> like: '2012-06-06 12:03:00+0000 %a2fc07', where the part after the '%' 
> character would be hexadecimal for the non-timestamp part of the UUID. 
> Understanding this syntax could allow to work with timeuuid uniquely with 
> meaningful date string which I think would be neat. But maybe that's a crazy 
> idea, opinions?

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