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From Ollif Lee <ollif...@gmail.com>
Subject Re: Purpose of BLOB datatype
Date Wed, 10 Jul 2013 09:59:56 GMT
fine, thanks.


On Tue, Jul 9, 2013 at 11:24 PM, Pavel Kirienko <
pavel.kirienko.list@gmail.com> wrote:

> > Do you know any direct ways in CQL to handle BLOB, just like DataStax
> Java driver?
>
> Well, CQL3 specification explicitly says that there is no way to encode
> blob into CQL request other than HEX string:
> http://cassandra.apache.org/doc/cql3/CQL.html#constants
>
>
>
> On Tue, Jul 9, 2013 at 6:40 PM, Ollif Lee <olliflee@gmail.com> wrote:
>
>> Thank you for your patience. That is what I have expected.
>> PS. Do you know any direct ways in CQL to handle BLOB, just like DataStax
>> Java driver?
>>
>>
>> On Tue, Jul 9, 2013 at 4:53 PM, Sylvain Lebresne <sylvain@datastax.com>wrote:
>>
>>> > Pls explain why and how.
>>>
>>> Why and how what?
>>>
>>> Not encoding blobs into strings is the "preferred way" because that's
>>> obviously
>>>  more efficient (in speed and space), since you don't do any encoding
>>> pass.
>>>
>>> As for how, "use prepared statement" was the "how". What are the exact
>>> lines of
>>> code to use to do prepared statements will depends on the client driver
>>> you
>>> use, and you should check your driver documentation.
>>>
>>> But, to give you an example, if you use the DataStax Java driver
>>> (https://github.com/datastax/java-driver), this might look something
>>> like:
>>>
>>>   PreparedStatement st = session.prepare("INSERT INTO foo(myKey, myBlob)
>>> VALUES (?, ?)");
>>>   String myKey = ...;
>>>   ByteBuffer myBlob = ...;
>>>   session.execute(st.bind(myKey, myBlob));
>>>
>>>
>>> --
>>> Sylvain
>>>
>>
>>
>

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