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From Roshan Dawrani <roshandawr...@gmail.com>
Subject Re: Retrieving TimeUUID sub-columns in reverse order
Date Sun, 26 Dec 2010 12:11:00 GMT
Hi Ran,
I am not doing it the YAML way. I am defining my SCF through Hector API as
below

================================================================
ThriftCfDef cfDef = HFactory.createColumnFamilyDefinition(ksName, "SCF")
cfDef.setColumnMetadata(...)
cfDef.setColumnType(ColumnType.SUPER)
cfDef.setSubComparatorType(ComparatorType.TIMEUUIDTYPE)
================================================================

And this is the structure of the SCF:
================================================================
"key1" :
          "superCol1":
                    SubColName1 (TimeUUID) : null
                    SubColName2 (TimeUUID) : null
                    SubColName3 (TimeUUID) : null
          "superCol2":
                    SubColName4 (TimeUUID) : null
                    SubColName5 (TimeUUID) : null
                    SubColName6 (TimeUUID) : null
================================================================

I now try to retrieve the data as below, but for both reverse = true |
false, it's only the order of supercolumns that changes. The subcolumns
always come in the same order - oldest to newest

================================================================
RangeSuperSlicesQuery#setRange (null, null, reverse, Integer.MAX_VALUE) //
reverse = true | false
================================================================

Anything I am doing wrong here?

-- 
Roshan
Blog: http://roshandawrani.wordpress.com/
Twitter: @roshandawrani <http://twitter.com/roshandawrani>
Skype: roshandawrani

On Sun, Dec 26, 2010 at 5:31 PM, Ran Tavory <rantav@gmail.com> wrote:

> Roshan, in cassandra.yaml did you define compare_subcolumns_with  for the
> SCF?
> The subcolumn names are the timeuuid, not the subcolumn values, right?
>
>
> On Sun, Dec 26, 2010 at 9:14 AM, Roshan Dawrani <roshandawrani@gmail.com>wrote:
>
>> Hi,
>>
>> I have a super ColumnFamily that has a few super columns, with each having
>> a growing list of sub-columns where column name is a TimeUUID, so the
>> sub-columns get stored chronologically (oldest to newest)
>>
>> When I retrieve this data, can I somehow retrieve the sub-columns in
>> reverse order - newest first?
>>
>> I am using RangeSuperSlicesQuery to query the super columns and setting a
>> range on it with *reverse = true*, but that only sorts the data by super
>> column names.
>>
>> How can I tell RangeSuperSlicesQuery to get the sub-columns also in
>> reverse order?
>>
>> Thanks.
>>
>> --
>> Roshan
>> Blog: http://roshandawrani.wordpress.com/
>> Twitter: @roshandawrani <http://twitter.com/roshandawrani>
>> Skype: roshandawrani
>>
>
>
>
> --
> /Ran
>
>

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