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From Eldad Yamin <elda...@gmail.com>
Subject Re: HOW TO select a column or all columns that start with X
Date Wed, 03 Aug 2011 12:35:40 GMT
Thanks!

On Wed, Aug 3, 2011 at 3:03 PM, aaron morton <aaron@thelastpickle.com>wrote:

> and AsciiType
>
>
> -----------------
> Aaron Morton
> Freelance Cassandra Developer
> @aaronmorton
> http://www.thelastpickle.com
>
> On 3 Aug 2011, at 16:35, eldad87 wrote:
>
> Thank you!
> Will this situation work only for UTF8Type comparator?
>
>
> On Wed, Aug 3, 2011 at 4:50 AM, Tyler Hobbs <tyler@datastax.com> wrote:
>
>> A minor correction:
>>
>> To get all columns starting with "ABC_", you would set column_start="ABC_"
>> and column_finish="ABC`" (the '`' character comes after '_'), and ignore the
>> last column in your results if it happened to be "ABC`".
>>
>> column_finish, or the "slice end" in other clients, is inclusive.  You
>> could of course use "ABC_~" as column_finish and avoid the check if you know
>> that you don't have column names like "ABC_~FOO" that you want to include.
>>
>>
>> On Tue, Aug 2, 2011 at 7:17 PM, aaron morton <aaron@thelastpickle.com>wrote:
>>
>>> Yup, thats a pretty common pattern. How exactly depends on the client you
>>> are using.
>>>
>>> Say you were using pycassam, you would do a get()
>>> http://pycassa.github.com/pycassa/api/pycassa/columnfamily.html#pycassa.columnfamily.ColumnFamily.get
>>>
>>> with column_start="ABC_" , count to whatever, and column_finish not
>>> provided.
>>>
>>> You can also provide a finish and use the highest encoded character, e.g.
>>> ascii 126 is ~ so if you used column_finish = "ABC_~" you would get
>>> everything that starts with ABC_
>>>
>>> Cheers
>>>
>>>  -----------------
>>> Aaron Morton
>>> Freelance Cassandra Developer
>>> @aaronmorton
>>> http://www.thelastpickle.com
>>>
>>> On 3 Aug 2011, at 09:28, Eldad Yamin wrote:
>>>
>>> Hello,
>>> I wonder if I can select a column or all columns that start with X.
>>> E.g I have columns ABC_1, ABC_2, ZZZ_1 and I want to select all columns
>>> that start with ABC_ - is that possible?
>>>
>>>
>>>
>>> Thanks!
>>>
>>>
>>>
>>
>>
>> --
>> Tyler Hobbs
>> Software Engineer, DataStax <http://datastax.com/>
>> Maintainer of the pycassa <http://github.com/pycassa/pycassa> Cassandra
>> Python client library
>>
>>
>
>

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