Save the skills in a single column in json format. Job done.
On Mar 26, 2012 7:04 PM, "Ben McCann" <b...@benmccann.com> wrote:
> True. But I don't need the skills to be searchable, so I'd rather embed
> them in the user than add another top-level CF. I was thinking of doing
> something along the lines of adding a skills super column to the User table:
>
> skills: {
> 'java': null,
> 'c++': null,
> 'cobol': null
> }
>
> However, I'm still not sure yet how to accomplish this with Astyanax.
> I've only figured out how to make composite columns with predefined column
> names with it and not dynamic column names like this.
>
>
>
> On Mon, Mar 26, 2012 at 9:08 AM, R. Verlangen <ro...@us2.nl> wrote:
>
>> In this case you only neem the columns for values. You don't need the
>> column-values to hold multiple columns (the super-column principle). So a
>> normal CF would work.
>>
>>
>> 2012/3/26 Ben McCann <b...@benmccann.com>
>>
>>> Thanks for the reply Samal. I did not realize that you could store a
>>> column with null value. Do you know if this solution would work with
>>> composite columns? It seems super columns are being phased out in favor of
>>> composites, but I do not understand composites very well yet. I'm trying
>>> to figure out if there's any way to accomplish what you've suggested using
>>> Astyanax <https://github.com/Netflix/astyanax>.
>>>
>>> Thanks for the help,
>>> Ben
>>>
>>>
>>> On Mon, Mar 26, 2012 at 8:46 AM, samal <samalgo...@gmail.com> wrote:
>>>
>>>> plus it is fully compatible with CQL.
>>>> SELECT * FROM UserSkill WHERE KEY='ben';
>>>>
>>>>
>>>> On Mon, Mar 26, 2012 at 9:13 PM, samal <samalgo...@gmail.com> wrote:
>>>>
>>>>> I would take simple approach. create one other CF "UserSkill" with
>>>>> row key same as profile_cf key,
>>>>> In user_skill cf will add skill as column name and value null. Columns
>>>>> can be added or removed.
>>>>>
>>>>> UserProfile={
>>>>> '*ben*'={
>>>>> blah :blah
>>>>> blah :blah
>>>>> blah :blah
>>>>> }
>>>>> }
>>>>>
>>>>> UserSkill={
>>>>> '*ben*'={
>>>>> 'java':''
>>>>> 'cassandra':''
>>>>> .
>>>>> .
>>>>> .
>>>>> 'linux':''
>>>>> 'skill':'infinity'
>>>>>
>>>>> }
>>>>>
>>>>> }
>>>>>
>>>>>
>>>>> On Mon, Mar 26, 2012 at 12:34 PM, Ben McCann <b...@benmccann.com>wrote:
>>>>>
>>>>>> I have a profile column family and want to store a list of skills in
>>>>>> each profile. In BigTable I could store a Protocol
>>>>>> Buffer<http://code.google.com/apis/protocolbuffers/docs/overview.html>with
>>>>>> a repeated field, but I'm not sure how this is typically accomplished
>>>>>> in Cassandra. One option would be to store a serialized
>>>>>> Thrift<http://thrift.apache.org/>or protobuf, but I'd prefer not to do
>>>>>> this as I believe Cassandra doesn't
>>>>>> have knowledge of these formats, and so the data in the datastore would
>>>>>> not
>>>>>> not human readable in CQL queries from the command line. The other
>>>>>> solution I thought of would be to use a super column and put a random
>>>>>> UUID
>>>>>> as the key for each skill:
>>>>>>
>>>>>> skills: {
>>>>>> '4b27c2b3ac48e8df': 'java',
>>>>>> '84bf94ea7bc92018': 'c++',
>>>>>> '9103b9a93ce9d18': 'cobol'
>>>>>> }
>>>>>>
>>>>>> Is this a good way of handling lists in Cassandra? I imagine there's
>>>>>> some idiom I'm not aware of. I'm using the
>>>>>> Astyanax<https://github.com/Netflix/astyanax/wiki>client library, which
>>>>>> only supports composite columns instead of super
>>>>>> columns, and so the solution I proposed above would seem quite awkward in
>>>>>> that case. Though I'm still having some trouble understanding composite
>>>>>> columns as they seem not to be completely documented yet. Would this
>>>>>> solution work with composite columns?
>>>>>>
>>>>>> Thanks,
>>>>>> Ben
>>>>>>
>>>>>>
>>>>>
>>>>
>>>
>>
>>
>> --
>> With kind regards,
>>
>> Robin Verlangen
>> www.robinverlangen.nl
>>
>>
>
