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From Christian Decker <decker.christ...@gmail.com>
Subject Re: LongType from user input
Date Thu, 30 Sep 2010 09:46:52 GMT
BTW is there an official Roadmap which states when the 0.7 release is to be
expected?

On Thu, Sep 30, 2010 at 11:38 AM, Christian Decker <
decker.christian@gmail.com> wrote:

> I just read through the tickets on Jira, and it appears that indices are
> implemented in the 0.7 source tree, but I cannot find any pointer on how to
> use them. I'll be trying to create a custom CassandraStorage that loads data
> through the indices, anyone else interested?
>
> Regards,
> Chris
>
>
> On Thu, Sep 30, 2010 at 10:56 AM, Aaron Morton <aaron@thelastpickle.com>wrote:
>
>> AFAIK indexes are still in dev. The only example is in the system_tests.py
>> in the source tree.
>>
>> Aaron
>>
>>
>> On 30 Sep 2010, at 20:10, Christian Decker <decker.christian@gmail.com>
>> wrote:
>>
>> Apparently I have blanked the 0.7 completely out of my memory. I was
>> trying to implement application layer indices and ignored the fact that
>> Cassandra 0.7 is implementing them by default. I found ticket CASSANDRA-749
>> about the indices and am reading through the code right now, but is there a
>> higher level overview and a tutorial on how to get things started with these
>> indices (and maybe some inner workings)? This might actually solve all of my
>> problems I'm having right now :-)
>>
>> Regards,
>> Chris
>>
>>
>> On Mon, Sep 27, 2010 at 3:45 AM, Aaron Morton < <aaron@thelastpickle.com>
>> aaron@thelastpickle.com> wrote:
>>
>>> The only thing I can think of is that values need to be in the correct
>>> byte format when used in indexes in 0.7. Take a look at the types.py module
>>> in the pycassa client  <http://github.com/pycassa/pycassa>
>>> http://github.com/pycassa/pycassa for an example of which values need to
>>> be byte packed.
>>>
>>> How is your pig function working against cassandra? Is it using the
>>> ColumnFamilyRecordReader? . The code in the internal RowIterator for that
>>> class has an example calling the cluster to get to the comparators.
>>>
>>> Aaron
>>>
>>>
>>> On 27 Sep, 2010,at 03:11 AM, Christian Decker <<decker.christian@gmail.com>
>>> decker.christian@gmail.com> wrote:
>>>
>>> Hi Aaron,
>>>
>>> what changes can I expect in the 0.7 release regarding Comparison and
>>> Parameters? My problem is mainly that I want to take Strings from stdin (or
>>> Pig Scripts for that matter) and convert them in such a way that they are
>>> interpreted correctly and converted to the corresponding byte representation
>>> to use them in column names and keys.
>>>
>>> Regards,
>>> Chris
>>>
>>> On Sun, Sep 26, 2010 at 5:20 AM, Aaron Morton <<aaron@thelastpickle.com>
>>> aaron@thelastpickle.com> wrote:
>>>
>>>> Things a changing in v0.7, the row keys are byte arrays.
>>>>
>>>> Not sure I understand your other concerns.
>>>>
>>>> Aaron
>>>>
>>>>
>>>> On 25 Sep 2010, at 08:10, Christian Decker <<decker.christian@gmail.com>
>>>> decker.christian@gmail.com> wrote:
>>>>
>>>>
>>>> Thanks for your quick answer, I think I'll use an affix to sort of cast
>>>> the keys, ranges and others from their textual representation (from Pig)
to
>>>> the desired byte representation, since I just noticed that the keys for the
>>>> rows themselfs are always UTF8 interpreted, and since I want to make
>>>> key-range as well as slice queries, I'll be better off this way I think.
>>>> I'll just add a 'L' for Long and 'U' for UUID (of any kind).
>>>>  Or is there a better way that I just can't see from my beginners angle?
>>>> :-)thing
>>>>
>>>> Regards,
>>>> Chris
>>>>
>>>>
>>>> On Fri, Sep 24, 2010 at 6:35 PM, Tyler Hobbs < <tyler@riptano.com><tyler@riptano.com>
>>>> tyler@riptano.com> wrote:
>>>>
>>>>> Yes, you can use describe_keyspace() and then look through the
>>>>> results.  It's a little ugly in 0.6, but it works
>>>>>
>>>>> - Tyler
>>>>>
>>>>>
>>>>>
>>>>> On Fri, Sep 24, 2010 at 11:25 AM, Christian Decker <<decker.christian@gmail.com><decker.christian@gmail.com>
>>>>> decker.christian@gmail.com> wrote:
>>>>>
>>>>>> Well I'm writing a loading function for Pig, and as it happens I
want
>>>>>> to be able to load slices from cassandra which are specified in the
pig
>>>>>> script (thus the input from stdin) but the ColumnFamily from which
to read
>>>>>> the data is another parameter and some of the CFs have UTF8, UUID,
TimeUUID
>>>>>> or Long types for their keys and columns, so simply converting everything
I
>>>>>> get to an 8byte long would break compatibility with the others.
>>>>>> Now thinking about it I attacked the whole problem in a weird way,
>>>>>> since UUID types won't work either.
>>>>>> So let me change my question slightly, is there a way in 0.6 to detect
>>>>>> the compareWith type on a running cluster? That way I could convert
it to
>>>>>> the right type :D
>>>>>>
>>>>>> Regards,
>>>>>> Chris
>>>>>>
>>>>>>
>>>>>> On Fri, Sep 24, 2010 at 6:09 PM, Tyler Hobbs < <tyler@riptano.com><tyler@riptano.com>
>>>>>> tyler@riptano.com> wrote:
>>>>>>
>>>>>>> I'm not sure I understand why using this with multiple column
>>>>>>> families prevents you from converting it.  Could you clarify
this?
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> On Fri, Sep 24, 2010 at 10:56 AM, Christian Decker <<decker.christian@gmail.com><decker.christian@gmail.com>
>>>>>>> decker.christian@gmail.com> wrote:
>>>>>>>
>>>>>>>> Hi all,
>>>>>>>>
>>>>>>>> I'm having quite a dilemma with the CompareWith attribute.
The
>>>>>>>> Problem is that I have numeric IDs that I'd like to use as
row keys, only
>>>>>>>> that I also have to offer a possibility to let users input
them from std
>>>>>>>> input. Since I cannot ask my users to input an 8byte sequence
representing
>>>>>>>> the ID they'd like, I was about to turn to UTF8, when I remembered
that they
>>>>>>>> are compared lexicographically, so that 100 actually comes
before 2, which
>>>>>>>> kills key slices. Also I cannot just code a converter in
since this is
>>>>>>>> supposed to be a used with multiple columnfamilies, so just
converting an
>>>>>>>> integer read into 8bytes isn't going to work either.
>>>>>>>> Any tricks for this one?
>>>>>>>>
>>>>>>>> Regards,
>>>>>>>> Chris
>>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>
>>>>>
>>>>
>>>
>>
>

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