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From Abhijit Chanda <abhijit.chan...@gmail.com>
Subject Re: How can I implement 'LIKE operation in SQL' on values while querying a column family in Cassandra
Date Wed, 16 May 2012 03:53:33 GMT
Sorry for the confusion Tamar. Any ways thanks dear.

Regards,
Abhijit

On Tue, May 15, 2012 at 9:36 PM, Tamar Fraenkel <tamar@tok-media.com> wrote:

> Actually woman ;-)
>
> *Tamar Fraenkel *
> Senior Software Engineer, TOK Media
>
> [image: Inline image 1]
>
> tamar@tok-media.com
> Tel:   +972 2 6409736
> Mob:  +972 54 8356490
> Fax:   +972 2 5612956
>
>
>
>
>
> On Tue, May 15, 2012 at 3:45 PM, Abhijit Chanda <abhijit.chanda0@gmail.com
> > wrote:
>
>> Thanks so much Guys, specially Tamar, thank you so much man.
>>
>> Regards,
>> Abhijit
>>
>>
>> On Tue, May 15, 2012 at 4:26 PM, Tamar Fraenkel <tamar@tok-media.com>wrote:
>>
>>> Do you still need the sample code? I use Hector, well here is an example:
>>> *This is the Column Family definition:*
>>> (I have a composite, but if you like you can have only the UTF8Type).
>>>
>>> CREATE COLUMN FAMILY title_indx
>>>     with comparator = 'CompositeType(UTF8Type,UUIDType)'
>>>     and default_validation_class = 'UTF8Type'
>>>     and key_validation_class = 'LongType';
>>>
>>> *The Query:*
>>>     SliceQuery<Long, Composite, String> query =
>>>             HFactory.createSliceQuery(CassandraHectorConn.getKeyspace(),
>>>                     LongSerializer.get(),
>>>                     CompositeSerializer.get(),
>>>                     StringSerializer.get());
>>>     query.setColumnFamily("title_indx");
>>>     query.setKey(...)
>>>
>>>     Composite start = new Composite();
>>>     start.add(prefix);
>>>     char c = lowerCasePrefix.charAt(lastCharIndex);
>>>     String prefixEnd =  prefix.substring(0, lastCharIndex) + ++c;
>>>     Composite end = new Composite();
>>>     end.add(prefixEnd);
>>>
>>>     ColumnSliceIterator<Long, Composite, String> iterator =
>>>               new ColumnSliceIterator<Long, Composite, String>(
>>>                        query, start, end, false)
>>>     while (iterator.hasNext()) {
>>>     ...
>>>    }
>>>
>>> Cheers,
>>>
>>> *Tamar Fraenkel *
>>> Senior Software Engineer, TOK Media
>>>
>>> [image: Inline image 1]
>>>
>>> tamar@tok-media.com
>>> Tel:   +972 2 6409736
>>> Mob:  +972 54 8356490
>>> Fax:   +972 2 5612956
>>>
>>>
>>>
>>>
>>>
>>> On Tue, May 15, 2012 at 1:19 PM, samal <samalgorai@gmail.com> wrote:
>>>
>>>> You cannot extract via relative column value.
>>>> It can only extract via value if it has secondary index but exact
>>>> column value need to match.
>>>>
>>>> as tamar suggested you can put value as column "name" , UTF8 comparator.
>>>>
>>>> {
>>>> 'name_abhijit'=>'abhijit'
>>>> 'name_abhishek'=>'abhiskek'
>>>> 'name_atul'=>'atul'
>>>> }
>>>>
>>>> here you can do slice query on column name and get desired result.
>>>>
>>>> /samal
>>>>
>>>> On Tue, May 15, 2012 at 3:29 PM, selam <selamtux@gmail.com> wrote:
>>>>
>>>>> Mapreduce jobs may solve your problem  for batch processing
>>>>>
>>>>>
>>>>> On Tue, May 15, 2012 at 12:49 PM, Abhijit Chanda <
>>>>> abhijit.chanda0@gmail.com> wrote:
>>>>>
>>>>>> Tamar,
>>>>>>
>>>>>> Can you please illustrate little bit with some sample code. It highly
>>>>>> appreciable.
>>>>>>
>>>>>> Thanks,
>>>>>>
>>>>>>
>>>>>> On Tue, May 15, 2012 at 10:48 AM, Tamar Fraenkel <tamar@tok-media.com
>>>>>> > wrote:
>>>>>>
>>>>>>> I don't think this is possible, the best you can do is prefix,
if
>>>>>>> your order is alphabetical. For example I have a CF with
>>>>>>> comparator UTF8Type, and then I can do slice query and bring
all columns
>>>>>>> that start with the prefix, and end with the prefix where you
replace the
>>>>>>> last char with the next one in order (i.e. "aaa"-"aab").
>>>>>>>
>>>>>>> Hope that helps.
>>>>>>>
>>>>>>> *Tamar Fraenkel *
>>>>>>> Senior Software Engineer, TOK Media
>>>>>>>
>>>>>>> [image: Inline image 1]
>>>>>>>
>>>>>>> tamar@tok-media.com
>>>>>>> Tel:   +972 2 6409736
>>>>>>> Mob:  +972 54 8356490
>>>>>>> Fax:   +972 2 5612956
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> On Tue, May 15, 2012 at 7:56 AM, Abhijit Chanda <
>>>>>>> abhijit.chanda0@gmail.com> wrote:
>>>>>>>
>>>>>>>> I don't know the exact value on a column, but I want to do
a
>>>>>>>> partial matching to know all available values that matches.
>>>>>>>> I want to do similar kind of operation that LIKE operator
in SQL
>>>>>>>> do.
>>>>>>>> Any help is highly appreciated.
>>>>>>>>
>>>>>>>> --
>>>>>>>> Abhijit Chanda
>>>>>>>> Software Developer
>>>>>>>> VeHere Interactive Pvt. Ltd.
>>>>>>>> +91-9748888395
>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>>>
>>>>>>
>>>>>> --
>>>>>> Abhijit Chanda
>>>>>> Software Developer
>>>>>> VeHere Interactive Pvt. Ltd.
>>>>>> +91-9748888395
>>>>>>
>>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> Saygılar && İyi Çalışmalar
>>>>> Timu EREN ( a.k.a selam )
>>>>>
>>>>
>>>>
>>>
>>
>>
>> --
>> Abhijit Chanda
>> Software Developer
>> VeHere Interactive Pvt. Ltd.
>> +91-9748888395
>>
>>
>


-- 
Abhijit Chanda
Software Developer
VeHere Interactive Pvt. Ltd.
+91-9748888395

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