Re: What is 'Read Reuqests' on OpsCenter exaclty?

[Carlos Rolo]

Let me try to reproduce your test and get back wiith some results.

Regards,

Carlos Juzarte Rolo
Cassandra Consultant

Pythian - Love your data

rolo@pythian | Twitter: cjrolo | Linkedin: *linkedin.com/in/carlosjuzarterolo
*
Mobile: +31 6 159 61 814 | Tel: +1 613 565 8696 x1649
www.pythian.com

On Fri, Apr 24, 2015 at 2:35 AM, Bongseo Jang  wrote:

> Thanks a lot Carlos, Sebastian :-)
>
> My test was with 1 node/1 replica settings, on which I assumed client
> request = read request on the graph. Because there seems no read_repair and
> already CL=ONE in my case, I need more explanation, don't I? Or can any
> other internals be still involved?
>
> Do you have more suggestions? I want to design new test narrowing the gap
> on the suggestions.
>
> On 24 April 2015 at 00:23, Sebastian Estevez <
> sebastian.este...@datastax.com> wrote:
>
>> Carlos is right:
>>
>> *Read Requests* - The number of read requests per second on the
>> coordinator nodes, analogous to client reads. Monitoring the number of
>> requests over a given time period reveals system read workload and usage
>> patterns.
>>
>> *Avg* - The average of values recorded during a time interval.
>>
>> A future version of OpsC will include tooltips with these descriptions
>> for better clarity.
>> On Apr 23, 2015 6:30 AM, "Carlos Rolo"  wrote:
>>
>>> Probably it takes in account the read repair, plus a read that have
>>> consistency != 1 will produce reads on other machines (which are taken in
>>> account). I don't know the internals of opscenter but I would assume that
>>> this is the case.
>>>
>>> If you want to test it further, disable read_repair, and make all your
>>> reads with CL=ONE. Then your client and Opscenter should match.
>>>
>>> PS: Speculative_retry could also send reads over to more machines.
>>>
>>> Regards,
>>>
>>> Carlos Juzarte Rolo
>>> Cassandra Consultant
>>>
>>> Pythian - Love your data
>>>
>>> rolo@pythian | Twitter: cjrolo | Linkedin: 
>>> *linkedin.com/in/carlosjuzarterolo
>>> *
>>> Mobile: +31 6 159 61 814 | Tel: +1 613 565 8696 x1649
>>> www.pythian.com
>>>
>>> On Thu, Apr 23, 2015 at 10:34 AM, Bongseo Jang 
>>> wrote:
>>>
 I have cassandra 2.1 + OpsCenter 5.1.1 and test them.

 When I monitored with opscenter 'read requests' graph, it seems the
 number on the graph is not what I expected, the number of client requests
 or responses.

 I recorded actual number of client request and compare it with graph,
 then found they're different. The number on the graph is about 4 times
 larger than what the client claimed.

 So, my question is what 'Read Reuqests' on OpsCenter counts exaclty ?

 Thanks !

 --
 Regards,
 Jang.

  a sound mind in a sound body

>>>
>>>
>>> --
>>>
>>>
>>>
>>>
>
>
> --
> Regards,
> Jang.
>
>  a sound mind in a sound body
>

-- 


--

Re: What is 'Read Reuqests' on OpsCenter exaclty?

[Bongseo Jang]

You're quite right. I missed important thing first.

I found a mistake in my program while making test case. It turns out that
the original program has 3~4 selects for non-existing row keys plus a
select for existing row key. It was intended to do nothing but for next
tests. My original test  counted only selects for existing row key but
opscenter graph showed real number of request. That's it

Thank you again ~

On 24 April 2015 at 16:01, Carlos Rolo  wrote:

> Let me try to reproduce your test and get back wiith some results.
>
> Regards,
>
> Carlos Juzarte Rolo
> Cassandra Consultant
>
> Pythian - Love your data
>
> rolo@pythian | Twitter: cjrolo | Linkedin: *linkedin.com/in/carlosjuzarterolo
> *
> Mobile: +31 6 159 61 814 | Tel: +1 613 565 8696 x1649
> www.pythian.com
>
> On Fri, Apr 24, 2015 at 2:35 AM, Bongseo Jang  wrote:
>
>> Thanks a lot Carlos, Sebastian :-)
>>
>> My test was with 1 node/1 replica settings, on which I assumed client
>> request = read request on the graph. Because there seems no read_repair and
>> already CL=ONE in my case, I need more explanation, don't I? Or can any
>> other internals be still involved?
>>
>> Do you have more suggestions? I want to design new test narrowing the gap
>> on the suggestions.
>>
>> On 24 April 2015 at 00:23, Sebastian Estevez <
>> sebastian.este...@datastax.com> wrote:
>>
>>> Carlos is right:
>>>
>>> *Read Requests* - The number of read requests per second on the
>>> coordinator nodes, analogous to client reads. Monitoring the number of
>>> requests over a given time period reveals system read workload and usage
>>> patterns.
>>>
>>> *Avg* - The average of values recorded during a time interval.
>>>
>>> A future version of OpsC will include tooltips with these descriptions
>>> for better clarity.
>>> On Apr 23, 2015 6:30 AM, "Carlos Rolo"  wrote:
>>>
 Probably it takes in account the read repair, plus a read that have
 consistency != 1 will produce reads on other machines (which are taken in
 account). I don't know the internals of opscenter but I would assume that
 this is the case.

 If you want to test it further, disable read_repair, and make all your
 reads with CL=ONE. Then your client and Opscenter should match.

 PS: Speculative_retry could also send reads over to more machines.

 Regards,

 Carlos Juzarte Rolo
 Cassandra Consultant

 Pythian - Love your data

 rolo@pythian | Twitter: cjrolo | Linkedin: 
 *linkedin.com/in/carlosjuzarterolo
 *
 Mobile: +31 6 159 61 814 | Tel: +1 613 565 8696 x1649
 www.pythian.com

 On Thu, Apr 23, 2015 at 10:34 AM, Bongseo Jang 
 wrote:

> I have cassandra 2.1 + OpsCenter 5.1.1 and test them.
>
> When I monitored with opscenter 'read requests' graph, it seems the
> number on the graph is not what I expected, the number of client requests
> or responses.
>
> I recorded actual number of client request and compare it with graph,
> then found they're different. The number on the graph is about 4 times
> larger than what the client claimed.
>
> So, my question is what 'Read Reuqests' on OpsCenter counts exaclty ?
>
> Thanks !
>
> --
> Regards,
> Jang.
>
>  a sound mind in a sound body
>


 --




>>
>>
>> --
>> Regards,
>> Jang.
>>
>>  a sound mind in a sound body
>>
>
>
> --
>
>
>
>


-- 
Regards,
Jang.

 a sound mind in a sound body

Re: What is 'Read Reuqests' on OpsCenter exaclty?

[Bongseo Jang]

I can see two numbers matches when the redundant selects are removed with 1
node/1 replica settings.

On 24 April 2015 at 19:09, Bongseo Jang  wrote:

> You're quite right. I missed important thing first.
>
> I found a mistake in my program while making test case. It turns out that
> the original program has 3~4 selects for non-existing row keys plus a
> select for existing row key. It was intended to do nothing but for next
> tests. My original test  counted only selects for existing row key but
> opscenter graph showed real number of request. That's it
>
> Thank you again ~
>
> On 24 April 2015 at 16:01, Carlos Rolo  wrote:
>
>> Let me try to reproduce your test and get back wiith some results.
>>
>> Regards,
>>
>> Carlos Juzarte Rolo
>> Cassandra Consultant
>>
>> Pythian - Love your data
>>
>> rolo@pythian | Twitter: cjrolo | Linkedin: *linkedin.com/in/carlosjuzarterolo
>> *
>> Mobile: +31 6 159 61 814 | Tel: +1 613 565 8696 x1649
>> www.pythian.com
>>
>> On Fri, Apr 24, 2015 at 2:35 AM, Bongseo Jang 
>> wrote:
>>
>>> Thanks a lot Carlos, Sebastian :-)
>>>
>>> My test was with 1 node/1 replica settings, on which I assumed client
>>> request = read request on the graph. Because there seems no read_repair and
>>> already CL=ONE in my case, I need more explanation, don't I? Or can any
>>> other internals be still involved?
>>>
>>> Do you have more suggestions? I want to design new test narrowing the
>>> gap on the suggestions.
>>>
>>> On 24 April 2015 at 00:23, Sebastian Estevez <
>>> sebastian.este...@datastax.com> wrote:
>>>
 Carlos is right:

 *Read Requests* - The number of read requests per second on the
 coordinator nodes, analogous to client reads. Monitoring the number of
 requests over a given time period reveals system read workload and usage
 patterns.

 *Avg* - The average of values recorded during a time interval.

 A future version of OpsC will include tooltips with these descriptions
 for better clarity.
 On Apr 23, 2015 6:30 AM, "Carlos Rolo"  wrote:

> Probably it takes in account the read repair, plus a read that have
> consistency != 1 will produce reads on other machines (which are taken in
> account). I don't know the internals of opscenter but I would assume that
> this is the case.
>
> If you want to test it further, disable read_repair, and make all your
> reads with CL=ONE. Then your client and Opscenter should match.
>
> PS: Speculative_retry could also send reads over to more machines.
>
> Regards,
>
> Carlos Juzarte Rolo
> Cassandra Consultant
>
> Pythian - Love your data
>
> rolo@pythian | Twitter: cjrolo | Linkedin: 
> *linkedin.com/in/carlosjuzarterolo
> *
> Mobile: +31 6 159 61 814 | Tel: +1 613 565 8696 x1649
> www.pythian.com
>
> On Thu, Apr 23, 2015 at 10:34 AM, Bongseo Jang 
> wrote:
>
>> I have cassandra 2.1 + OpsCenter 5.1.1 and test them.
>>
>> When I monitored with opscenter 'read requests' graph, it seems the
>> number on the graph is not what I expected, the number of client requests
>> or responses.
>>
>> I recorded actual number of client request and compare it with graph,
>> then found they're different. The number on the graph is about 4 times
>> larger than what the client claimed.
>>
>> So, my question is what 'Read Reuqests' on OpsCenter counts exaclty ?
>>
>> Thanks !
>>
>> --
>> Regards,
>> Jang.
>>
>>  a sound mind in a sound body
>>
>
>
> --
>
>
>
>
>>>
>>>
>>> --
>>> Regards,
>>> Jang.
>>>
>>>  a sound mind in a sound body
>>>
>>
>>
>> --
>>
>>
>>
>>
>
>
> --
> Regards,
> Jang.
>
>  a sound mind in a sound body
>



-- 
Regards,
Jang.

 a sound mind in a sound body

Re: Creating 'Put' requests

[Phil Yang]

2015-04-23 22:16 GMT+08:00 Matthew Johnson :
>
> In HBase, we do something like:
>
> Put put = new Put(id);
> put.add(myPojo.getTimestamp(), myPojo.getValue());
> put.add(myPojo.getMySecondTimestamp(), myPojo.getSecondValue());
> server.put(put);
>
> Is there any similar mechanism in Cassandra Java driver for creating these
> inserts programmatically? Or, can the 'session.execute' take a list of
> commands so that each column can be inserted as its own insert statement
> but
> without the overhead of multiple calls to the server?
>
>

For your first question, do you mean object-mapping API?
http://docs.datastax.com/en/developer/java-driver/2.1/java-driver/reference/crudOperations.html

For the second question, C* can execute several commands by unlogged batch,
however, because of the distributed nature of Cassandra, there is a better
solution, see
https://medium.com/@foundev/cassandra-batch-loading-without-the-batch-keyword-40f00e35e23e




> Thanks!
> Matt
>
>
> -Original Message-
> From: Jim Witschey [mailto:jim.witsc...@datastax.com]
> Sent: 23 April 2015 14:46
> To: user@cassandra.apache.org
> Subject: Re: Creating 'Put' requests
>
> Are prepared statements what you're looking for?
>
>
> http://docs.datastax.com/en/developer/java-driver/2.1/java-driver/quick_start/qsSimpleClientBoundStatements_t.html
> Jim Witschey
>
> Software Engineer in Test | jim.witsc...@datastax.com
>
>
>
>
>
> On Thu, Apr 23, 2015 at 9:28 AM, Matthew Johnson 
> wrote:
> > Hi all,
> >
> >
> >
> > Currently looking at switching from HBase to Cassandra, and one big
> > difference so far is that in HBase, we create a ‘Put’ object, add to
> > it a set of column/value pairs, and send the Put to the server. So far
> > in Cassandra 2.1.4 the tutorials seem to suggest using CQL3, which I
> > really like for prototyping eg:
> >
> >
> >
> > session.execute("INSERT INTO simplex.playlists (id, song_id, title,
> > album,
> > artist) VALUES (1,1,'La Petite Tonkinoise','Bye Bye
> > Blackbird','Joséphine Baker');");
> >
> >
> >
> > But for more complicated code this will quickly become unmanageable,
> > and doesn’t lend itself well to dynamically creating row data based on
> > various conditions. Is there a way to send a Java object, populated
> > with the desired column/value pairs, to the server instead of executing
> an
> > insert statement?
> > Would this require some other library, or does the DataStax Java
> > driver support this already?
> >
> >
> >
> > Thanks in advance,
> >
> > Matt
> >
> >
>



-- 
Thanks,
Phil Yang

Re: Creating 'Put' requests

[Jens Rantil]

Matthew,

Maybe this could also be of interest:
http://projects.spring.io/spring-data-cassandra/

Cheers,
Jens

On Fri, Apr 24, 2015 at 12:50 PM, Phil Yang  wrote:

>
>
> 2015-04-23 22:16 GMT+08:00 Matthew Johnson :
>>
>> In HBase, we do something like:
>>
>> Put put = new Put(id);
>> put.add(myPojo.getTimestamp(), myPojo.getValue());
>> put.add(myPojo.getMySecondTimestamp(), myPojo.getSecondValue());
>> server.put(put);
>>
>> Is there any similar mechanism in Cassandra Java driver for creating these
>> inserts programmatically? Or, can the 'session.execute' take a list of
>> commands so that each column can be inserted as its own insert statement
>> but
>> without the overhead of multiple calls to the server?
>>
>>
>
> For your first question, do you mean object-mapping API?
> http://docs.datastax.com/en/developer/java-driver/2.1/java-driver/reference/crudOperations.html
>
> For the second question, C* can execute several commands by unlogged
> batch, however, because of the distributed nature of Cassandra, there is a
> better solution, see
> https://medium.com/@foundev/cassandra-batch-loading-without-the-batch-keyword-40f00e35e23e
>
>
>
>
>> Thanks!
>> Matt
>>
>>
>> -Original Message-
>> From: Jim Witschey [mailto:jim.witsc...@datastax.com]
>> Sent: 23 April 2015 14:46
>> To: user@cassandra.apache.org
>> Subject: Re: Creating 'Put' requests
>>
>> Are prepared statements what you're looking for?
>>
>>
>> http://docs.datastax.com/en/developer/java-driver/2.1/java-driver/quick_start/qsSimpleClientBoundStatements_t.html
>> Jim Witschey
>>
>> Software Engineer in Test | jim.witsc...@datastax.com
>>
>>
>>
>>
>>
>> On Thu, Apr 23, 2015 at 9:28 AM, Matthew Johnson > >
>> wrote:
>> > Hi all,
>> >
>> >
>> >
>> > Currently looking at switching from HBase to Cassandra, and one big
>> > difference so far is that in HBase, we create a ‘Put’ object, add to
>> > it a set of column/value pairs, and send the Put to the server. So far
>> > in Cassandra 2.1.4 the tutorials seem to suggest using CQL3, which I
>> > really like for prototyping eg:
>> >
>> >
>> >
>> > session.execute("INSERT INTO simplex.playlists (id, song_id, title,
>> > album,
>> > artist) VALUES (1,1,'La Petite Tonkinoise','Bye Bye
>> > Blackbird','Joséphine Baker');");
>> >
>> >
>> >
>> > But for more complicated code this will quickly become unmanageable,
>> > and doesn’t lend itself well to dynamically creating row data based on
>> > various conditions. Is there a way to send a Java object, populated
>> > with the desired column/value pairs, to the server instead of executing
>> an
>> > insert statement?
>> > Would this require some other library, or does the DataStax Java
>> > driver support this already?
>> >
>> >
>> >
>> > Thanks in advance,
>> >
>> > Matt
>> >
>> >
>>
>
>
>
> --
> Thanks,
> Phil Yang
>
>


-- 
Jens Rantil
Backend engineer
Tink AB

Email: jens.ran...@tink.se
Phone: +46 708 84 18 32
Web: www.tink.se

Facebook  Linkedin

 Twitter 

Re: Creating 'Put' requests

[Jonathan Haddad]

There's also Achilles: https://github.com/doanduyhai/Achilles

On Fri, Apr 24, 2015 at 1:21 PM Jens Rantil  wrote:

> Matthew,
>
> Maybe this could also be of interest:
> http://projects.spring.io/spring-data-cassandra/
>
> Cheers,
> Jens
>
> On Fri, Apr 24, 2015 at 12:50 PM, Phil Yang  wrote:
>
>>
>>
>> 2015-04-23 22:16 GMT+08:00 Matthew Johnson :
>>>
>>> In HBase, we do something like:
>>>
>>> Put put = new Put(id);
>>> put.add(myPojo.getTimestamp(), myPojo.getValue());
>>> put.add(myPojo.getMySecondTimestamp(), myPojo.getSecondValue());
>>> server.put(put);
>>>
>>> Is there any similar mechanism in Cassandra Java driver for creating
>>> these
>>> inserts programmatically? Or, can the 'session.execute' take a list of
>>> commands so that each column can be inserted as its own insert statement
>>> but
>>> without the overhead of multiple calls to the server?
>>>
>>>
>>
>> For your first question, do you mean object-mapping API?
>> http://docs.datastax.com/en/developer/java-driver/2.1/java-driver/reference/crudOperations.html
>>
>> For the second question, C* can execute several commands by unlogged
>> batch, however, because of the distributed nature of Cassandra, there is a
>> better solution, see
>> https://medium.com/@foundev/cassandra-batch-loading-without-the-batch-keyword-40f00e35e23e
>>
>>
>>
>>
>>> Thanks!
>>> Matt
>>>
>>>
>>> -Original Message-
>>> From: Jim Witschey [mailto:jim.witsc...@datastax.com]
>>> Sent: 23 April 2015 14:46
>>> To: user@cassandra.apache.org
>>> Subject: Re: Creating 'Put' requests
>>>
>>> Are prepared statements what you're looking for?
>>>
>>>
>>> http://docs.datastax.com/en/developer/java-driver/2.1/java-driver/quick_start/qsSimpleClientBoundStatements_t.html
>>> Jim Witschey
>>>
>>> Software Engineer in Test | jim.witsc...@datastax.com
>>>
>>>
>>>
>>>
>>>
>>> On Thu, Apr 23, 2015 at 9:28 AM, Matthew Johnson <
>>> matt.john...@algomi.com>
>>> wrote:
>>> > Hi all,
>>> >
>>> >
>>> >
>>> > Currently looking at switching from HBase to Cassandra, and one big
>>> > difference so far is that in HBase, we create a ‘Put’ object, add to
>>> > it a set of column/value pairs, and send the Put to the server. So far
>>> > in Cassandra 2.1.4 the tutorials seem to suggest using CQL3, which I
>>> > really like for prototyping eg:
>>> >
>>> >
>>> >
>>> > session.execute("INSERT INTO simplex.playlists (id, song_id, title,
>>> > album,
>>> > artist) VALUES (1,1,'La Petite Tonkinoise','Bye Bye
>>> > Blackbird','Joséphine Baker');");
>>> >
>>> >
>>> >
>>> > But for more complicated code this will quickly become unmanageable,
>>> > and doesn’t lend itself well to dynamically creating row data based on
>>> > various conditions. Is there a way to send a Java object, populated
>>> > with the desired column/value pairs, to the server instead of
>>> executing an
>>> > insert statement?
>>> > Would this require some other library, or does the DataStax Java
>>> > driver support this already?
>>> >
>>> >
>>> >
>>> > Thanks in advance,
>>> >
>>> > Matt
>>> >
>>> >
>>>
>>
>>
>>
>> --
>> Thanks,
>> Phil Yang
>>
>>
>
>
> --
> Jens Rantil
> Backend engineer
> Tink AB
>
> Email: jens.ran...@tink.se
> Phone: +46 708 84 18 32
> Web: www.tink.se
>
> Facebook  Linkedin
> 
>  Twitter 
>

Re: Creating 'Put' requests

[Jonathan Haddad]

To add to Phil's point, there's no circumstance in which I would use an
unlogged batch, under load I have yet to hear it do anything other than
increase GC pauses.

On Fri, Apr 24, 2015 at 11:50 AM Phil Yang  wrote:

> 2015-04-23 22:16 GMT+08:00 Matthew Johnson :
>>
>> In HBase, we do something like:
>>
>> Put put = new Put(id);
>> put.add(myPojo.getTimestamp(), myPojo.getValue());
>> put.add(myPojo.getMySecondTimestamp(), myPojo.getSecondValue());
>> server.put(put);
>>
>> Is there any similar mechanism in Cassandra Java driver for creating these
>> inserts programmatically? Or, can the 'session.execute' take a list of
>> commands so that each column can be inserted as its own insert statement
>> but
>> without the overhead of multiple calls to the server?
>>
>>
>
> For your first question, do you mean object-mapping API?
> http://docs.datastax.com/en/developer/java-driver/2.1/java-driver/reference/crudOperations.html
>
> For the second question, C* can execute several commands by unlogged
> batch, however, because of the distributed nature of Cassandra, there is a
> better solution, see
> https://medium.com/@foundev/cassandra-batch-loading-without-the-batch-keyword-40f00e35e23e
>
>
>
>
>> Thanks!
>> Matt
>>
>>
>> -Original Message-
>> From: Jim Witschey [mailto:jim.witsc...@datastax.com]
>> Sent: 23 April 2015 14:46
>> To: user@cassandra.apache.org
>> Subject: Re: Creating 'Put' requests
>>
>> Are prepared statements what you're looking for?
>>
>>
>> http://docs.datastax.com/en/developer/java-driver/2.1/java-driver/quick_start/qsSimpleClientBoundStatements_t.html
>> Jim Witschey
>>
>> Software Engineer in Test | jim.witsc...@datastax.com
>>
>>
>>
>>
>>
>> On Thu, Apr 23, 2015 at 9:28 AM, Matthew Johnson > >
>> wrote:
>> > Hi all,
>> >
>> >
>> >
>> > Currently looking at switching from HBase to Cassandra, and one big
>> > difference so far is that in HBase, we create a ‘Put’ object, add to
>> > it a set of column/value pairs, and send the Put to the server. So far
>> > in Cassandra 2.1.4 the tutorials seem to suggest using CQL3, which I
>> > really like for prototyping eg:
>> >
>> >
>> >
>> > session.execute("INSERT INTO simplex.playlists (id, song_id, title,
>> > album,
>> > artist) VALUES (1,1,'La Petite Tonkinoise','Bye Bye
>> > Blackbird','Joséphine Baker');");
>> >
>> >
>> >
>> > But for more complicated code this will quickly become unmanageable,
>> > and doesn’t lend itself well to dynamically creating row data based on
>> > various conditions. Is there a way to send a Java object, populated
>> > with the desired column/value pairs, to the server instead of executing
>> an
>> > insert statement?
>> > Would this require some other library, or does the DataStax Java
>> > driver support this already?
>> >
>> >
>> >
>> > Thanks in advance,
>> >
>> > Matt
>> >
>> >
>>
>
>
>
> --
> Thanks,
> Phil Yang
>
>

RE: Creating 'Put' requests

[Matthew Johnson]

The object-mapping API is very interesting, I’ll check that out, thanks. I
believe I have found what I was looking for in terms of programmatically
inserting data using the following syntax:



*  Insert builder = QueryBuilder.insertInto(**"simplex"**, *
*"mytable1"**);*

*  builder = builder.value(**"id"**, **"myid2"**);*

*  builder = builder.value(**"title"**, **"mytitle2"**);*

  *session**.execute(builder);*



Many thanks for all the valuable help so far!



Cheers,

Matt



*From:* Jonathan Haddad [mailto:j...@jonhaddad.com]
*Sent:* 24 April 2015 14:15
*To:* user@cassandra.apache.org
*Subject:* Re: Creating 'Put' requests



To add to Phil's point, there's no circumstance in which I would use an
unlogged batch, under load I have yet to hear it do anything other than
increase GC pauses.

On Fri, Apr 24, 2015 at 11:50 AM Phil Yang  wrote:

2015-04-23 22:16 GMT+08:00 Matthew Johnson :

In HBase, we do something like:

Put put = new Put(id);
put.add(myPojo.getTimestamp(), myPojo.getValue());
put.add(myPojo.getMySecondTimestamp(), myPojo.getSecondValue());
server.put(put);

Is there any similar mechanism in Cassandra Java driver for creating these
inserts programmatically? Or, can the 'session.execute' take a list of
commands so that each column can be inserted as its own insert statement but
without the overhead of multiple calls to the server?





For your first question, do you mean object-mapping API?
http://docs.datastax.com/en/developer/java-driver/2.1/java-driver/reference/crudOperations.html



For the second question, C* can execute several commands by unlogged batch,
however, because of the distributed nature of Cassandra, there is a better
solution, see
https://medium.com/@foundev/cassandra-batch-loading-without-the-batch-keyword-40f00e35e23e






Thanks!
Matt



-Original Message-
From: Jim Witschey [mailto:jim.witsc...@datastax.com]
Sent: 23 April 2015 14:46
To: user@cassandra.apache.org
Subject: Re: Creating 'Put' requests

Are prepared statements what you're looking for?

http://docs.datastax.com/en/developer/java-driver/2.1/java-driver/quick_start/qsSimpleClientBoundStatements_t.html
Jim Witschey

Software Engineer in Test | jim.witsc...@datastax.com





On Thu, Apr 23, 2015 at 9:28 AM, Matthew Johnson 
wrote:
> Hi all,
>
>
>
> Currently looking at switching from HBase to Cassandra, and one big
> difference so far is that in HBase, we create a ‘Put’ object, add to
> it a set of column/value pairs, and send the Put to the server. So far
> in Cassandra 2.1.4 the tutorials seem to suggest using CQL3, which I
> really like for prototyping eg:
>
>
>
> session.execute("INSERT INTO simplex.playlists (id, song_id, title,
> album,
> artist) VALUES (1,1,'La Petite Tonkinoise','Bye Bye
> Blackbird','Joséphine Baker');");
>
>
>
> But for more complicated code this will quickly become unmanageable,
> and doesn’t lend itself well to dynamically creating row data based on
> various conditions. Is there a way to send a Java object, populated
> with the desired column/value pairs, to the server instead of executing an
> insert statement?
> Would this require some other library, or does the DataStax Java
> driver support this already?
>
>
>
> Thanks in advance,
>
> Matt
>
>





-- 

Thanks,

Phil Yang

Confirming Repairs

[Jeff Ferland]

The short answer is I used a logstash query to get a list of all repair
ranges started and all ranges completed. I then matched the UUID of the
start message to the end message and printed out all the ranges that didn't
succeed. Then one needs to go a step further than I've coded and match the
remaining ranges to at least one node in the ring that would hold a replica
for the keyspace.

Does anybody have a better way to handle this yet? Will the 3.0 series
logging of repairs to the system keyspace be able to give me this same kind
of confirmation that everything in a given keyspace was last repaired as of
$DATE, or that to repair everything as of $DATE I must repair ranges $X?

https://gist.github.com/autocracy/9467eaaff581ff24334c

Re: Confirming Repairs

[Yuki Morishita]

In 3.0, we have system table that stores repair history.
https://issues.apache.org/jira/browse/CASSANDRA-5839
So you can just use CQL to check when given ks/cf is repaired.

On Sat, Apr 25, 2015 at 5:23 AM, Jeff Ferland  wrote:
> The short answer is I used a logstash query to get a list of all repair
> ranges started and all ranges completed. I then matched the UUID of the
> start message to the end message and printed out all the ranges that didn't
> succeed. Then one needs to go a step further than I've coded and match the
> remaining ranges to at least one node in the ring that would hold a replica
> for the keyspace.
>
> Does anybody have a better way to handle this yet? Will the 3.0 series
> logging of repairs to the system keyspace be able to give me this same kind
> of confirmation that everything in a given keyspace was last repaired as of
> $DATE, or that to repair everything as of $DATE I must repair ranges $X?
>
> https://gist.github.com/autocracy/9467eaaff581ff24334c



-- 
Yuki Morishita
 t:yukim (http://twitter.com/yukim)