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From Mahesh Daksha <daks...@gmail.com>
Subject Re: ***UNCHECKED*** Query regarding cassandra column write time set by client Timestamp Generator
Date Tue, 09 Apr 2019 09:47:18 GMT
Thank you Ben and Varun. Will try these approaches.

On Tue, Apr 9, 2019 at 3:12 PM Varun Barala <varunbarala99@gmail.com> wrote:

> I'm not sure about the use cases. But other approaches can also be
> considered:-
>
> * Every mutation will have the timestamp in the commitlog [So taking
> backup of the commitlogs will give you this functionality]
> * At client side, you fetch the existing writetime for those columns from
> the db and also log the actual timestamp which is associated with the
> current update/insert statements
> https://docs.datastax.com/en/drivers/java/3.6/com/datastax/driver/core/Statement.html#getDefaultTimestamp--
> (though this should only be used for debugging purposes!)
>
>
> Thanks!
>
> On Tue, Apr 9, 2019 at 5:31 PM Ben Slater <ben.slater@instaclustr.com>
> wrote:
>
>> Maybe stabledump can help you?
>> https://cassandra.apache.org/doc/4.0/tools/sstable/sstabledump.html
>>
>> ---
>>
>>
>> *Ben Slater*
>> *Chief Product Officer*
>>
>>
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>>
>> On Tue, 9 Apr 2019 at 19:26, Mahesh Daksha <dakshme@gmail.com> wrote:
>>
>>> Thanks Ben for your response.
>>> WRITETIME  gives the information of about the column value already
>>> residing int the table. We intend to know  the timestamp of the record
>>> which is about to apply/update.
>>> This is needed to understand the timestamp difference of the data
>>> residing in table with the one going to overwite the same.
>>>
>>> This all information is needed as out update statements going silent
>>> (not reflecting any changes) in database. Not even returning any error or
>>> exception.
>>>
>>> Thanks,
>>> Mahesh Daksha
>>>
>>> On Tue, Apr 9, 2019 at 2:46 PM Ben Slater <ben.slater@instaclustr.com>
>>> wrote:
>>>
>>>> Not in the logs but I think you should be able to use the WRITETIME
>>>> function to view via CQL (see
>>>> https://cassandra.apache.org/doc/latest/cql/dml.html#select)
>>>>
>>>> Cheers
>>>> Ben
>>>>
>>>> ---
>>>>
>>>>
>>>> *Ben Slater*
>>>> *Chief Product Officer*
>>>>
>>>>
>>>> <https://www.facebook.com/instaclustr>
>>>> <https://twitter.com/instaclustr>
>>>> <https://www.linkedin.com/company/instaclustr>
>>>>
>>>> Read our latest technical blog posts here
>>>> <https://www.instaclustr.com/blog/>.
>>>>
>>>> This email has been sent on behalf of Instaclustr Pty. Limited
>>>> (Australia) and Instaclustr Inc (USA).
>>>>
>>>> This email and any attachments may contain confidential and legally
>>>> privileged information.  If you are not the intended recipient, do not copy
>>>> or disclose its content, but please reply to this email immediately and
>>>> highlight the error to the sender and then immediately delete the message.
>>>>
>>>>
>>>> On Tue, 9 Apr 2019 at 16:51, Mahesh Daksha <dakshme@gmail.com> wrote:
>>>>
>>>>> Hello,
>>>>>
>>>>> I have configured the timestamp generator at cassandra client as below:
>>>>>
>>>>> cluster.setTimestampGenerator(new AtomicMonotonicTimestampGenerator());
>>>>>
>>>>>
>>>>> My cassandra client inserting and updating few of the rows in a table.
>>>>> My query is where in the cassandra debug logs I can see the query
>>>>> write time associated by with updated columns in the update query (sent
by
>>>>> cient). Or if there is any other way I can log the same at client
>>>>> itself.
>>>>>
>>>>> Basically I want to see the write time sent by client to cassandra
>>>>> cluster.
>>>>>
>>>>> Thanks,
>>>>> Mahesh Daksha
>>>>>
>>>>

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