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From Patricio Echagüe <patric...@gmail.com>
Subject Re: Is it possible to read from one row, several SuperColumns with all their Columns in one call?
Date Thu, 22 Jul 2010 19:01:09 GMT
Hey thanks Aaron. It finally worked. The API reference looked a bit
confusing to me.

I used (as you suggested):
                    ColumnParent parent = new ColumnParent(
<ColumnFamily name>);
                    SlicePredicate sp = new SlicePredicate();
                    sp.setColumn_names( <list of super column names>);

after calling get_slice() ....as result, i got the super columns I
passed in the list with ALLl their columns in one call.

so now, just IF I WANTED TO, would it be possible to get just a subset
of columns contained in those supercolumns instead of all of them
assuming that the amount of columns are lot and for performance issues
i want to avoid moving a lot of data over the network?

2010/7/22 Patricio Echagüe <patricioe@gmail.com>:
> Hi Aaron, the problem I have is that those UUIDs are random numbers.
> 2,3,4 are not sequential unfortunately. I don't think there is an API
> like mutiget_slice for key but for Super Column names.
>
> Is there any other way to specify a list of super column names to read
> where those names are not sequential?
>
> thanks
>
>
> On Wed, Jul 21, 2010 at 5:58 PM, Aaron Morton <aaron@thelastpickle.com> wrote:
>> Take a look at the  get_slice  function http://wiki.apache.org/cassandra/API
>>
>> You could send one with a ColumnParent that only specifies the ColumnFamily
>> and a SlicePredicate with a SliceRange where the start and finish values are
>> empty strings. Set the count to an appropriate level to get them all (e.g.
>> 1000) or make multiple calls.
>>
>>
>> Aaron
>>
>>
>> On 22 Jul, 2010,at 12:05 PM, Patricio Echagüe <patricioe@gmail.com> wrote:
>>
>> Hi all, apologize before hand if this question sounds a bit dumb but I
>> don't see what API I should use (if there is any)
>>
>> this is my model:
>>
>> row key A:
>> SC_UUID_1:
>> Col1, Col2, Col3
>> SC_UUID_2:
>> Col1, Col2, Col3
>> SC_UUID_3:
>> Col1, Col2, Col3
>> SC_UUID_4:
>> Col1, Col2, Col3
>> SC_UUID_5:
>> Col1, Col2, Col3
>>
>> SC_UUID(i) are random UUIDs.
>>
>> Is there any way to read in one call from row A, the SC 2,3,4 with all
>> their columns? The amount of columns in every SuperColumn is not big
>> at all. normally less than 20.
>>
>> Thanks
>> --
>> Patricio-
>>
>
>
>
> --
> Patricio.-
>



-- 
Patricio.-

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