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From eldad87 <elda...@gmail.com>
Subject Re: HOW TO select a column or all columns that start with X
Date Wed, 03 Aug 2011 06:35:09 GMT
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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