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From Carl Mueller <carl.muel...@smartthings.com.INVALID>
Subject Re: TTL on UDT
Date Mon, 09 Dec 2019 20:36:03 GMT
Oh right frozen vs unfrozen.

On Mon, Dec 9, 2019 at 2:23 PM DuyHai Doan <doanduyhai@gmail.com> wrote:

> It depends on.. Latest version of Cassandra allows unfrozen UDT. The
> individual fields of UDT are updated atomically and they are stored
> effectively in distinct physical columns inside the partition, thus
> applying ttl() on them makes sense. I'm not sure however if the CQL parser
> allows this syntax
>
> On Mon, Dec 9, 2019 at 9:13 PM Carl Mueller
> <carl.mueller@smartthings.com.invalid> wrote:
>
>> I could be wrong, but UDTs I think are written (and overwritten) as one
>> unit, so the notion of a TTL on a UDT field doesn't exist, the TTL is
>> applied to the overall structure.
>>
>> Think of it like a serialized json object with multiple fields. To update
>> a field they deserialize the json, then reserialize the json with the new
>> value, and the whole json object has the new timestamp or ttl.
>>
>> On Tue, Dec 3, 2019 at 10:02 AM Mark Furlong <mfurlong@ancestry.com>
>> wrote:
>>
>>> When I run the command ‘select ttl(udt_field) from table; I’m getting an
>>> error ‘InvalidRequest: Error from server: code=2200 [Invalid query]
>>> message="Cannot use selection function ttl on collections"’. How can I get
>>> the TTL from a UDT field?
>>>
>>>
>>>
>>> *Mark Furlong*
>>>
>>>
>>>
>>>
>>>
>>> We empower journeys of personal discovery to enrich lives
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>>>
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>>

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