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From Ben McCann <...@benmccann.com>
Subject Re: How to store a list of values?
Date Wed, 28 Mar 2012 08:11:42 GMT
Hmm. I thought that Cassandra would encode the composite column without the
colon and that it was only there for illustration purposes, so the
suggestion to use ~ is confusing.  Are there some docs you can point me to?
 Also, after some reading, it seems to me that it is not even possible to
have a composite column together with a regular column in a column family
in this manner.


On Wed, Mar 28, 2012 at 12:34 AM, R. Verlangen <robin@us2.nl> wrote:

> Yes, that is one of the possible solutions to your problem.
>
> When you want to retrieve only the skills of a particular row just get the
> columns with as start value "skill:".
>
> A suggestion to your example might be to use a ~ in stead of : as
> separator. A tilde is used less often in standard sentences, so you could
> replace any of them in skills with some other character (e.g. a dash or
> whitespace).
>
> 2012/3/27 Ben McCann <ben@benmccann.com>
>
>> I was given one other suggestion (which may have been suggested earlier
>> in this thread, but is clearer to me with an example).  The suggestion was
>> to use composite columns and have the first part of the key name be "skill"
>> and the second part be the specific skill and then store a null value.  I
>> hope I understood this suggestion correctly.
>>
>> user: {
>>   'name': 'ben',
>>   'title': 'software engineer',
>>   'company': 'google',
>>   'location': 'orange county',
>>   'skill:java': '',
>>   'skill:html': '',
>>   'skill:javascript': ''
>> }
>>
>>
>> On Tue, Mar 27, 2012 at 12:04 AM, samal <samalgorai@gmail.com> wrote:
>>
>>> YEAH! agree, it only matter for time bucket data.
>>>
>>>
>>> On Tue, Mar 27, 2012 at 12:31 PM, R. Verlangen <robin@us2.nl> wrote:
>>>
>>>> That's true, but it does not sound like a real problem to me.. Maybe
>>>> someone else can shed some light upon this.
>>>>
>>>>
>>>> 2012/3/27 samal <samalgorai@gmail.com>
>>>>
>>>>>
>>>>>
>>>>> On Tue, Mar 27, 2012 at 1:47 AM, R. Verlangen <robin@us2.nl> wrote:
>>>>>
>>>>>> " but any schema change will break it "
>>>>>>
>>>>>> How do you mean? You don't have to specify the columns in Cassandra
>>>>>> so it should work perfect. Except for the "skill~" is preserverd
for your
>>>>>> list.
>>>>>>
>>>>>
>>>>>  In case skill~ is decided to change to skill:: , it need to be handle
>>>>> at app level. Or otherwise had t update in all row, read it first, modify
>>>>> it, insert new version and delete old version.
>>>>>
>>>>>
>>>>
>>>>
>>>> --
>>>> With kind regards,
>>>>
>>>> Robin Verlangen
>>>> www.robinverlangen.nl
>>>>
>>>>
>>>
>>
>
>
> --
> With kind regards,
>
> Robin Verlangen
> www.robinverlangen.nl
>
>

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