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From Ali Akhtar <ali.rac...@gmail.com>
Subject Re: Using a Set for UDTs, how is uniqueness established?
Date Mon, 07 Nov 2016 12:32:51 GMT
Huh, so that means updates to the udt values won't be possible?

Sticking to a map<string, udt> then.

On Mon, Nov 7, 2016 at 5:31 PM, DuyHai Doan <doanduyhai@gmail.com> wrote:

> So, to compare UDT values, Cassandra will compare them field by field. So
> that udt1.equals(udt2) results in:
>
>       udt1.field1.equals(udt2.field1)
> && udt1.field2.equals(udt2.field2)
> ...
> && udt1.fieldN.equals(udt2.fieldN)
>
> Your idea of using field "id" to distinguish between UDT value is good
> e.g. if the "id" value mismatches then the 2 UDT are different. However, if
> the "id" values do match, it does not guarantee that the UDT values match
> since it requires that all other fields match.
>
>
>
> On Mon, Nov 7, 2016 at 1:14 PM, Ali Akhtar <ali.rac200@gmail.com> wrote:
>
>> I have a UDT which contains a text 'id' field, which should be used to
>> establish the uniqueness of the UDT.
>>
>> I'd like to have a set<my_udt> field in a table, and I'd like to use the
>> id of the udts to establish uniqueness.
>>
>> Any ideas how this can be done? Also using Java, and c* 3.7
>>
>
>

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