Re: Are Writes disk-bound rather than CPU-bound?
I see pretty much the same formulation in the 1.2 docs, so I'm wondering what would be the best rewrite of that paragraph? On Tue, Jul 23, 2013 at 9:00 AM, hajjat wrote: > > > On Tue, Jul 23, 2013 at 5:05 AM, aaron morton [via [hidden > email]<http://user/SendEmail.jtp?type=node&node=7589248&i=0>] > <[hidden email] <http://user/SendEmail.jtp?type=node&node=7589248&i=1>>wrote: > >> “/Insert-heavy workloads will actually be CPU-bound in Cassandra before >> being >> memory-bound/” >> >> What is the source for that ? > > > http://www.datastax.com/docs/0.8/cluster_architecture/cluster_planning > > >> >> This is because everything is >> *first *written to the commit log *on disk*. Any thoughts?? >> >> Pretty much. >> >> Cheers >> >>- >> Aaron Morton >> Cassandra Consultant >> New Zealand >> >> @aaronmorton >> http://www.thelastpickle.com >> >> On 22/07/2013, at 8:58 AM, hajjat <[hidden >> email]<http://user/SendEmail.jtp?type=node&node=7589236&i=0>> >> wrote: >> >> “/Insert-heavy workloads will actually be CPU-bound in Cassandra before >> being >> memory-bound/” >> >> However, from reading the documentation >> (http://www.datastax.com/docs/1.2/dml/about_writes) it seems the disk is >> the >> real bottleneck in Writes rather than the CPU. This is because everything >> is >> *first *written to the commit log *on disk*. Any thoughts?? >> >> >> >> -- >> View this message in context: >> http://cassandra-user-incubator-apache-org.3065146.n2.nabble.com/Are-Writes-disk-bound-rather-than-CPU-bound-tp7589191.html >> Sent from the [hidden >> email]<http://user/SendEmail.jtp?type=node&node=7589236&i=1>mailing list >> archive at >> Nabble.com. >> >> >> >> >> -- >> If you reply to this email, your message will be added to the >> discussion below: >> >> http://cassandra-user-incubator-apache-org.3065146.n2.nabble.com/Are-Writes-disk-bound-rather-than-CPU-bound-tp7589191p7589236.html >> To unsubscribe from Are Writes disk-bound rather than CPU-bound?, click >> here. >> NAML<http://cassandra-user-incubator-apache-org.3065146.n2.nabble.com/template/NamlServlet.jtp?macro=macro_viewer&id=instant_html%21nabble%3Aemail.naml&base=nabble.naml.namespaces.BasicNamespace-nabble.view.web.template.NabbleNamespace-nabble.view.web.template.NodeNamespace&breadcrumbs=notify_subscribers%21nabble%3Aemail.naml-instant_emails%21nabble%3Aemail.naml-send_instant_email%21nabble%3Aemail.naml> >> > > > > -- > *Mohammad Hajjat* > *Ph.D. Student* > *Electrical and Computer Engineering* > *Purdue University* > > -- > View this message in context: Re: Are Writes disk-bound rather than > CPU-bound?<http://cassandra-user-incubator-apache-org.3065146.n2.nabble.com/Are-Writes-disk-bound-rather-than-CPU-bound-tp7589191p7589248.html> > > Sent from the cassandra-u...@incubator.apache.org mailing list > archive<http://cassandra-user-incubator-apache-org.3065146.n2.nabble.com/>at > Nabble.com. > -- :- a) Alex Popescu @al3xandru
Re: Is there update-in-place on maps?
On Wed, Aug 7, 2013 at 10:47 AM, Aaron Morton wrote: > As for the atomic increment, I take the answer is 'no, there is no atomic > increment, I have to pull the value to the client and send an update with > the new value'. > > Saying "atomic increment" is probably confusing. > You cannot have Counters, the thing most people would think about when you > say "increment", in a collection type. > > You can update the values in a map server side. > > If you can provide a concrete example of what you want to do it may be > easier. > > I think the OP is asking if the following op is atomic: UPDATE users SET favs['posts'] = favs['post'] + 1 WHERE id = 'smith' :- a) Cheers > > - > Aaron Morton > Cassandra Consultant > New Zealand > > @aaronmorton > http://www.thelastpickle.com > > On 6/08/2013, at 10:05 PM, Andy Twigg wrote: > > Counters can be atomically incremented ( > http://wiki.apache.org/cassandra/Counters). Pick a UUID for the counter, > and use that: c=map.get(k); c.incr() > > > On 6 August 2013 11:01, Jan Algermissen wrote: > >> >> On 06.08.2013, at 11:36, Andy Twigg wrote: >> >> > Store pointers to counters as map values? >> >> Sorry, but this fits into nothing I know about C* so far - can you >> explain? >> >> Jan >> >> > > > -- > Dr Andy Twigg > Junior Research Fellow, St Johns College, Oxford > Room 351, Department of Computer Science > http://www.cs.ox.ac.uk/people/andy.twigg/ > andy.tw...@cs.ox.ac.uk | +447799647538 > > > -- :- a) Alex Popescu Sen. Product Manager @ DataStax @al3xandru
Re: Any good GUI based tool to manage data in Casandra?
I've seen your email last week and saved it to ping you about DevCenter: http://www.datastax.com/dev/blog/introducing-datastax-devcenter. Please keep in mind that this is just the first version and we need suggestions/bug reports/etc. :- a) On Wed, Aug 7, 2013 at 11:18 AM, Tony Anecito wrote: > Thanks Nick for your reply. Good to know that. I knew OpsCenter was mainly > schema management. > > Best Regards, > -Tony > > > -- > *From:* Nick Bailey > *To:* user@cassandra.apache.org > *Sent:* Wednesday, August 7, 2013 12:04 PM > > *Subject:* Re: Any good GUI based tool to manage data in Casandra? > > OpsCenter allows CRUD of column families themselves (although not CQL3 > column families). It only allows viewing the data inside column families > though, no support for writing or updating. > > > On Wed, Aug 7, 2013 at 12:54 PM, Aaron Morton wrote: > > I think on of the versions of ops centre has the feature > http://www.datastax.com/what-we-offer/products-services/datastax-opscenter > > otherwise people use the cassandra-cli or cqlsh. > > Cheers > > - > Aaron Morton > Cassandra Consultant > New Zealand > > @aaronmorton > http://www.thelastpickle.com > > On 7/08/2013, at 1:28 AM, Tony Anecito wrote: > > Thanks Aaron. I found that before I asked the question and Helenos seems > the closest but it does not allow you to easily use CRUD like say SQL > Server Management tools where you can get a list of say 1,000 records in a > grid control and select rows for deletion or insert or update. > > I will look closer at that one since this is the reply from the team but > if users on this email list have other suggestions please do not hesitate > to reply. > > Many Thanks, > -Tony > > *From:* Aaron Morton > *To:* Cassandra User > *Sent:* Tuesday, August 6, 2013 1:38 AM > *Subject:* Re: Any good GUI based tool to manage data in Casandra? > > There is a list here. > > http://wiki.apache.org/cassandra/Administration%20Tools > > Cheers > > - > Aaron Morton > Cassandra Consultant > New Zealand > > @aaronmorton > http://www.thelastpickle.com/ > > On 3/08/2013, at 6:19 AM, Tony Anecito wrote: > > Hi All, > > Is there a GUI tool for managing data in Cassandra database? I have google > and seen tools but they seem to be schema management or explorer to just > view data. IT would be great to delete/inset rows or update values for a > column via GUI. > > Thanks, > -Tony > > > > > > > > > -- :- a) Alex Popescu Sen. Product Manager @ DataStax @al3xandru
Re: Any good GUI based tool to manage data in Casandra?
DevCenter is using the new java driver [1] which works only with CQL3 and the binary protocol so older C*/DSE version will not be supported. I know that upgrading your cluster just to be able to use DevCenter doesn't make sense, but hopefully features in the 1.2 and 2.0 will justify the upgrade ;-) [1] https://github.com/datastax/java-driver On Fri, Aug 9, 2013 at 10:02 AM, Rahul Gupta wrote: > Hello, > > ** ** > > Is there backward compatibility planned for DataStax DevCenter. > > I am using DSE 3.0.1 and Cassandra 1.1.9.7 > > ** ** > > Currently no plan to upgrade to C* 1.2. > > ** ** > > Thanks, > > *Rahul Gupta* > *DEKA* *Research & Development* <http://www.dekaresearch.com/> > > 340 Commercial St Manchester, NH 03101 > > P: 603.666.3908 extn. 6504 | C: 603.718.9676 > > ** ** > > This e-mail and the information, including any attachments, it contains > are intended to be a confidential communication only to the person or > entity to whom it is addressed and may contain information that is > privileged. If the reader of this message is not the intended recipient, > you are hereby notified that any dissemination, distribution or copying of > this communication is strictly prohibited. If you have received this > communication in error, please immediately notify the sender and destroy > the original message. > > ** ** > > *From:* Alex Popescu [mailto:al...@datastax.com] > *Sent:* Friday, August 09, 2013 12:47 AM > *To:* user@cassandra.apache.org; Tony Anecito > > *Subject:* Re: Any good GUI based tool to manage data in Casandra? > > ** ** > > I've seen your email last week and saved it to ping you about DevCenter: > http://www.datastax.com/dev/blog/introducing-datastax-devcenter. Please > keep in mind that this is just the first version and we need > suggestions/bug reports/etc. > > ** ** > > :- a) > > ** ** > > On Wed, Aug 7, 2013 at 11:18 AM, Tony Anecito wrote: > > > Thanks Nick for your reply. Good to know that. I knew OpsCenter was mainly > schema management. > > Best Regards, > -Tony > > ** ** > > ** ** >-- > > *From:* Nick Bailey > *To:* user@cassandra.apache.org > *Sent:* Wednesday, August 7, 2013 12:04 PM > > > *Subject:* Re: Any good GUI based tool to manage data in Casandra? > > ** ** > > OpsCenter allows CRUD of column families themselves (although not CQL3 > column families). It only allows viewing the data inside column families > though, no support for writing or updating. > > ** ** > > On Wed, Aug 7, 2013 at 12:54 PM, Aaron Morton > wrote: > > I think on of the versions of ops centre has the feature > http://www.datastax.com/what-we-offer/products-services/datastax-opscenter > > > ** ** > > otherwise people use the cassandra-cli or cqlsh. > > ** ** > > Cheers > > ** ** > > - > > Aaron Morton > > Cassandra Consultant > > New Zealand > > ** ** > > @aaronmorton > > http://www.thelastpickle.com > > ** ** > > On 7/08/2013, at 1:28 AM, Tony Anecito wrote: > > > > > > Thanks Aaron. I found that before I asked the question and Helenos seems > the closest but it does not allow you to easily use CRUD like say SQL > Server Management tools where you can get a list of say 1,000 records in a > grid control and select rows for deletion or insert or update. > > > > I will look closer at that one since this is the reply from the team but > if users on this email list have other suggestions please do not hesitate > to reply. > > > > Many Thanks, > > -Tony > > ** ** > > *From:* Aaron Morton > *To:* Cassandra User > *Sent:* Tuesday, August 6, 2013 1:38 AM > *Subject:* Re: Any good GUI based tool to manage data in Casandra? > > ** ** > > There is a list here. > > ** ** > > http://wiki.apache.org/cassandra/Administration%20Tools > > ** ** > > Cheers > > ** ** > > - > > Aaron Morton > > Cassandra Consultant > > New Zealand > > ** ** > > @aaronmorton > > http://www.thelastpickle.com/ > > ** ** > > On 3/08/2013, at 6:19 AM, Tony Anecito wrote: > > > > > > Hi All, > > ** ** > > Is there a GUI tool for managing data in Cassandra database? I have google > and seen tools but they seem to be schema management or explorer to just > view data. IT would be great
Re: Any good GUI based tool to manage data in Casandra?
On Fri, Aug 9, 2013 at 10:12 AM, David McNelis wrote: > Is DevCenter a project that might end up open sourced? The original blog > post calls it free, and if its destined to stay so, I'd think that would be > a benefit (being OSS) to the community at large. > > > We haven't figured this part yet. DevCenter is still in its infancy and we'll be experimenting with different approaches/technologies to allow us to build the features we imagined for it. Having the code in the open right now doesn't make too much sense. -- :- a) Alex Popescu Sen. Product Manager @ DataStax @al3xandru
Re: Any good GUI based tool to manage data in Casandra?
It surely is coming! Being an early version we wanted to focus on nailing a couple of things first before supporting multiple OS versions. On Fri, Aug 9, 2013 at 1:11 PM, Keith Freeman <8fo...@gmail.com> wrote: > Sounds like a good tool, but isn't it odd to only have Windows & Mac > versions? My impression has been that most users run Cassandra on Linux. > Is a Linux version coming (please!)? > > > On 08/09/2013 01:27 PM, Alex Popescu wrote: > > > On Fri, Aug 9, 2013 at 10:12 AM, David McNelis wrote: > >> Is DevCenter a project that might end up open sourced? The original blog >> post calls it free, and if its destined to stay so, I'd think that would be >> a benefit (being OSS) to the community at large. >> >> >> > We haven't figured this part yet. DevCenter is still in its infancy and > we'll be experimenting with different approaches/technologies to allow us > to build the features we imagined for it. Having the code in the open right > now doesn't make too much sense. > > -- > > :- a) > > > Alex Popescu > Sen. Product Manager @ DataStax > @al3xandru > > > -- :- a) Alex Popescu Sen. Product Manager @ DataStax @al3xandru
Re: CQL: Prepared statements
On Wed, Aug 28, 2013 at 4:01 AM, Vassilis Bekiaris < bekiar...@iconplatforms.com> wrote: > Hi, > > I think the introductory paragraphs in the Java Driver documentation [1] > provide good justification on the use of prepared statements: > > " ... but you can also use prepared statements, which only need to be > parsed once by the cluster, and then bind values to the variables and > execute the bound statement you read or write data to a cluster. > > In the previous tutorial, you added a loadData method which creates a new > statement for each INSERT, but you may also use prepared statements and > bind new values to the columns each time before execution. Doing this > increases performance, especially for repeated queries." > > Cheers! > > [1] > http://www.datastax.com/documentation/developer/java-driver/1.0/webhelp/index.html#java-driver/quick_start/qsSimpleClientBoundStatements_t.html > > > I think PreparedStatements should almost always be the recommended way (no stringification, performance, etc.). Except maybe statements that you are sure they'll be run only once, :- a) Alex Popescu @al3xandru
Re: CQL & Thrift
On Fri, Aug 30, 2013 at 11:56 AM, Vivek Mishra wrote: > @lhazlewood > > https://issues.apache.org/jira/browse/CASSANDRA-5959 > > Begin batch > > multiple insert statements. > > apply batch > > It doesn't work for you? > > -Vivek > > According to the OP batching inserts is slow. The SO thread [1] mentions that the in their environment BATCH takes 1.5min, while the Thrift-based approach is around 235millis. [1] http://stackoverflow.com/questions/18522191/using-cassandra-and-cql3-how-do-you-insert-an-entire-wide-row-in-a-single-reque -- :- a) Alex Popescu Sen. Product Manager @ DataStax @al3xandru
Re: is this correct, thrift unportable to CQL3Š.
sing the value but it didn't work :(
>>
>> Right, because not providing a value is akin to having a null value (in
>> the CQL3 sense of the term, which is different from what Dean asked about)
>> and null values are not allowed for primary key columns.
>> You could however insert an *empty* value if you wanted, which in you
>> case is just inserting an empty string since colname is a string. Thrift
>> doesn't allow more or less in that case.
>>
>> --
>> Sylvain
>>
>>
>>
>> So our code is like below where we are using 3 values if colname is not
>> null..else 2 values..
>>
>> if (key != null) {
>> PreparedStatement statement = session.prepare("INSERT
>> INTO keys.StringIndice (id, colname, colvalue) VALUES (?, ?, ?)");
>> BoundStatement boundStatement = new
>> BoundStatement(statement);
>>
>> session.execute(boundStatement.bind(StandardConverters.convertFromBytes(String.class,
>> rowKey), key, ByteBuffer.wrap(value)));
>> } else {
>> PreparedStatement statement = session.prepare("INSERT
>> INTO " + keys + "." + table + "(id, colvalue) VALUES (?, ?)");
>> BoundStatement boundStatement = new
>> BoundStatement(statement);
>>
>> session.execute(boundStatement.bind(StandardConverters.convertFromBytes(String.class,
>> rowKey), ByteBuffer.wrap(value)));
>> }
>>
>> And, I did that and getting this exception:
>>
>> Exception:Missing PRIMARY KEY part colname since colvalue is set
>>
>> And just FYI. Our Column Family definition is below:
>>
>> CREATE TABLE keys.StringIndice (id text,
>> colname text,
>> colvalue blob,
>> PRIMARY KEY (id,colname, colvalue)) WITH COMPACT STORAGE)
>>
>> Thanks again,
>> Vikas Goyal
>>
>>
>>
>> On Tue, Sep 24, 2013 at 7:02 PM, Sylvain Lebresne > <mailto:sylv...@datastax.com>> wrote:
>> Short answer: not, this is not correct.
>>
>> Longer answer: what you call "null" is actually an empty value (which is
>> *not* the same thing, unless you consider an empty string is the same thing
>> than a null string). As it happens, C* always an empty value as a valid
>> value for any type and that's true of both thrift and CQL3. What is true is
>> that CQL3 discourage the use of empty values for type for which it doesn't
>> particularly make sense (integers typically) by not having a particular
>> easy to use syntax to input them. But that's supported nonetheless. If you
>> use a prepared statement for instance (where you send values already
>> serialized), nothing will prevent you from sending an empty value. Even if
>> you don't want to use a prepared statement, CQL3 has conversion functions (
>> http://cassandra.apache.org/doc/cql3/CQL.html#blobFun) that allows to do
>> it (for instance, "blobAsInt(0x)" will be an empty int value).
>>
>> --
>> Sylvain
>>
>>
>>
>> On Tue, Sep 24, 2013 at 2:36 PM, Hiller, Dean > <mailto:dean.hil...@nrel.gov>> wrote:
>> Many applications in thrift use the wide row with composite column name
>> and as an example, let's say golf score for instance and we end up with
>> golf score : pk like so
>>
>> null : pk56
>> null : pk45
>> 89 : pk90
>> 89: pk87
>> 90: pk101
>> 95: pk17
>>
>> Notice that there are some who do not have a golf score(zero would not
>> quite make sense and would be interpreted as a golf score). I am hearing
>> from this post if they are correct that this is not portable to CQL3??? Is
>> this true?
>> http://stackoverflow.com/questions/18963248/how-can-i-have-null-column-value-for-a-composite-key-column-in-cql3
>>
>> (This sounds like a major deficit to me as the wide row now can only be
>> used where actual values exist?). Is it possible to port this pattern
>> to CQL3?
>>
>> Thanks,
>> Dean
>>
>>
>>
>>
>>
>>
>>
>>
>
--
:- a)
Alex Popescu
Sen. Product Manager @ DataStax
@al3xandru
Re: CQL Tables in Cassandra with an Index
Conditional inserts/updates (lightweight transactions) are available only
in C* 2.0+.
Also most of the time you should try to think about alternative ways to
solve the problem and rely on these only if you cannot find a different
solution (the reason for this is that they come with performance penalties
and you'd be better off with a scalable & performant design, rather than
taking the easy way out ;-)
On Fri, Nov 8, 2013 at 11:40 AM, Techy Teck wrote:
> If I execute the above query from CQL shell, it doesn't work for me at
> all... This is what I get -
>
> cqlsh:pp> insert into test_new (employee_id, employee_name, value,
> last_modified_date) values ('1', 'e29', 'some_new_value', now()) if not
> exists
> ;
> Bad Request: line 1:123 missing EOF at 'if'
>
> Is there anything I am missing here? I am running Cassandra 1.2.3
>
>
>
>
> On Fri, Nov 8, 2013 at 5:33 AM, DuyHai Doan wrote:
>
>> Consider using the new lightweight transaction
>>
>> insert into test_new (employee_id, employee_name, value,
>> last_modified_date) values ('1', 'e29', 'some_new_value', now()) *if
>> not exists*;
>>
>>
>>
>> Le vendredi 8 novembre 2013 03:53:12 UTC+1, Techy Teck a écrit :
>>
>>> I am using the below table in our use case -
>>>
>>> create table test_new (
>>> employee_id text,
>>> employee_name text,
>>> value text,
>>> last_modified_date timeuuid,
>>> primary key (employee_id, last_modified_date)
>>>);
>>>
>>> create index employee_name_idx on test_new (employee_name);
>>>
>>> In my above table employee_id will be unique always starting from 1 till
>>> 32767. So our query pattern is like this -
>>>
>>> 1. Give me everything for any of the employee_id?
>>> 2. Give me everything for what has changed in last 5 minutes?
>>> 3. Give me everything for any of the employee_name?
>>>
>>>
>>> I will be inserting below data into my above table -
>>>
>>> insert into test_new (employee_id, employee_name, value,
>>> last_modified_date) values ('1', 'e27', 'some_value', now());
>>> insert into test_new (employee_id, employee_name, value,
>>> last_modified_date) values ('2', 'e27', 'some_new_value', now());
>>> insert into test_new (employee_id, employee_name, value,
>>> last_modified_date) values ('3', 'e28', 'some_new_again_value', now());
>>>
>>> So now is there any way to avoid this particular scenario in my above
>>> table for the below query.. Somehow somebody by mistake is trying to
>>> execute the below query then it will create another row with employee_id as
>>> 1 and with other fields? I don't want anyone to insert the same employee_id
>>> again if it is already there in the cassandra database.. Any thoughts?
>>>
>>> insert into test_new (employee_id, employee_name, value,
>>> last_modified_date) values ('1', 'e29', 'some_new_value', now());
>>>
>>>
>>> To unsubscribe from this group and stop receiving emails from it, send
>> an email to java-driver-user+unsubscr...@lists.datastax.com.
>>
>
> To unsubscribe from this group and stop receiving emails from it, send an
> email to java-driver-user+unsubscr...@lists.datastax.com.
>
--
:- a)
Alex Popescu
Sen. Product Manager @ DataStax
@al3xandru
Re: Counters question - is there a better way to count
On Thu, Dec 5, 2013 at 7:44 AM, Christopher Wirt wrote: > I want to build a really simple column family which counts the occurrence > of a single event X. > > The guys from Disqus are big into counters: https://www.youtube.com/watch?v=A2WdS0YQADo http://www.slideshare.net/planetcassandra/cassandra-at-disqus (relevant slides start at 25) -- :- a) Alex Popescu @al3xandru
Re: How to retrieve snappy compressed data from Cassandra using Datastax?
Wouldn't you be better to delegate the compression part to Cassandra (which
support Snappy [1])? This way the compression part will be completely
transparent to your application.
[1] http://www.datastax.com/dev/blog/whats-new-in-cassandra-1-0-compression
On Tue, Jan 28, 2014 at 8:51 PM, Check Peck wrote:
> I am working on a project in which I am supposed to store the snappy
> compressed data in Cassandra, so that when I retrieve the same data from
> Cassandra, it should be snappy compressed in memory and then I will
> decompress that data using snappy to get the actual data from it.
>
> I am having a byte array in `bytesToStore` variable, then I am snappy
> compressing it using google `Snappy` and stored it back into Cassandra -
>
> // .. some code here
> System.out.println(bytesToStore);
>
> byte[] compressed = Snappy.compress(bytesToStore);
>
> attributesMap.put("e1", compressed);
>
> ICassandraClient client = CassandraFactory.getInstance().getDao();
> // write to Cassandra
> client.upsertAttributes("0123", attributesMap, "sample_table");
>
> After inserting the data in Cassandra, I went back into CQL mode and I
> queried it and I can see this data in my table for the test_id `0123`-
>
> cqlsh:testingks> select * from sample_table where test_id = '0123';
>
> test_id | name | value
>
> -+-+
> 0123 | e1 |
> 0x2cac7fff012c4ebb9555001e42797465204172726179205465737420466f722042696720456e6469616e
>
>
> Now I am trying to read the same data back from Cassandra and everytime it
> is giving me `IllegalArgumentException` -
>
> public Map getDataFromCassandra(final String rowKey,
> final Collection attributeNames) {
>
> Map dataFromCassandra = new
> ConcurrentHashMap();
>
> try {
> String query="SELECT test_id, name, value from sample_table
> where test_id = '"+rowKey+ "';";
> //SELECT test_id, name, value from sample_table where test_id
> = '0123';
> System.out.println(query);
>
> DatastaxConnection.getInstance();
>
> ResultSet result =
> DatastaxConnection.getSession().execute(query);
>
> Iterator it = result.iterator();
>
> while (it.hasNext()) {
> Row r = it.next();
> for(String str : attributeNames) {
> ByteBuffer bb = r.getBytes(str); // this line is
> throwing an exception for me
> byte[] ba=new byte[bb.remaining()];
> bb.get(ba, 0, ba.length);
> dataFromCassandra.put(str, ba);
> }
> }
> } catch (Exception e) {
> e.printStackTrace();
> }
>
> return dataFromCassandra;
> }
>
> This is the Exception I am getting -
>
> java.lang.IllegalArgumentException: e1 is not a column defined in this
> metadata
>
> In the above method, I am passing rowKey as `0123` and `attributeNames`
> contains `e1` as the string.
>
> I am expecting Snappy Compressed data in `dataFromCassandra` Map. In this
> map the key should be `e1` and the value should be snappy compressed data
> if I am not wrong.. And then I will iterate this Map to snappy decompress
> the data..
>
> I am using Datastax Java client working with Cassandra 1.2.9.
>
> Any thoughts what wrong I am doing here?
>
> To unsubscribe from this group and stop receiving emails from it, send an
> email to java-driver-user+unsubscr...@lists.datastax.com.
>
--
:- a)
Alex Popescu
Sen. Product Manager @ DataStax
@al3xandru
Re: Cassandra 2.0 with Hadoop 2.x?
On Thu, Feb 6, 2014 at 3:50 PM, Clint Kelly wrote: > I can > post a link if anyone is curious (once it is done). > I'm curious... thanks -- :- a) @al3xandru
Re: Driver documentation questions
While this is a question that would fit better on the Java driver group [1], I'll try to provide a very short answer: 1. Cluster is an long-lived object and the application should have only 1 instance 2. Session is also a long-lived object and you should try to have 1 Session per keyspace. A session manages connection pools for nodes in the cluster and it's an expensive resource. 2.1. In case your application uses a lot of keyspaces, then you should try to limit the number of Sessions and use fully qualified identifiers 3. PreparedStatements should be prepared only once. Session and PreparedStatements are thread-safe and should be shared across your app. [1] https://groups.google.com/a/lists.datastax.com/forum/#!forum/java-driver-user On Fri, Mar 7, 2014 at 12:42 PM, Green, John M (HP Education) < john.gr...@hp.com> wrote: > I’ve been tinkering with both the C++ and Java drivers but in neither > case have I got a good indication of how threading and resource mgmt should > be implemented in a long-lived multi-threaded application server > process.That is, what should be the scope of a builder, a cluster, > session, and statement. A JDBC connection is typically a per-thread > affair.When application server receives a request, it typically > > a) gets JDBC connection from a connection pool, > > b) processes the request > > c) returns the connection to the JDBC connection pool. > > > > All the Cassandra driver sample code I’ve seen so far is for single > threaded command-line applications so I’m wondering what is thread safe (if > anything) and what objects are “expensive” to instantiate. I’m assuming a > Session is analogous to a JDBC connection so when a request comes into my > multi-threaded application server, I should create a new Session (or find a > way to pool Sessions), but should I be creating a new cluster first? What > about a builder? > > > > John “lost in the abyss” > -- :- a) Alex Popescu Sen. Product Manager @ DataStax @al3xandru
Re: Exception in thread event_loop
Sundeep,
You'll probably have better chances to get these questions answered on the
Python driver group:
https://groups.google.com/a/lists.datastax.com/forum/#!forum/python-driver-user
1. I'd suggest rewriting a bit the first code snippet just to get it to
work first so we can eliminate other possible issues.
2. It looks like an installation issue of libev.
On Sun, Mar 16, 2014 at 7:01 PM, Sundeep Kambhampati <
satyasunde...@gmail.com> wrote:
>
> Thank you for the reply. I installed libev. However, it throwing a new
> exception. I searched online but couldn't find much help.
>
> File "Utils/readDataCassandra.py", line 6, in
> from cassandra.io.libevreactor import LibevConnection
> File
> "/usr/local/lib/python2.7/site-packages/cassandra/io/libevreactor.py", line
> 17, in
> import cassandra.io.libevwrapper as libev
> ImportError:
> /usr/local/lib/python2.7/site-packages/cassandra/io/libevwrapper.so:
> undefined symbol: ev_run
>
> Can you please help me with this?
>
> Regards,
> Sundeep
>
>
>
>
> On Sun, Mar 16, 2014 at 8:33 PM, Laing, Michael > wrote:
>
>> A possible workaround - not a fix - might be to install libev so the
>> libev event loop is used.
>>
>> See http://datastax.github.io/python-driver/installation.html
>>
>> Also be sure you are running the latest version: 1.0.2 I believe.
>>
>> Your ';' is outside of your 'str' - actually shouldn't be a problem tho.
>>
>> Good luck!
>> ml
>>
>>
>> On Sun, Mar 16, 2014 at 8:19 PM, Sundeep Kambhampati <
>> satyasunde...@gmail.com> wrote:
>>
>>> Hi,
>>>
>>> I am using cassandra-2.0.4.
>>>
>>> When I execute following python code, I often get an exception mentioned
>>> below. Sometimes it works fine but most of the times it throws an error.
>>> All the nodes are up and running. Data in second column of table is huge,
>>> few thousand characters long and there around 10K rows.
>>>
>>> Code :
>>>
>>> from cassandra.cluster import Cluster
>>>
>>> cluster = Cluster(['10.2.252.0', '10.2.252.1'])
>>> session = cluster.connect('test')
>>>
>>> str = "SELECT * FROM users ";
>>> rows = session.execute(str)
>>>
>>> for user_row in rows:
>>> print user_row.f_id, user_row.data
>>>
>>> cluster.shutdown()
>>>
>>> Exception:
>>>
>>> Exception in thread event_loop (most likely raised during interpreter
>>> shutdown):
>>> Traceback (most recent call last):
>>> File "/usr/local/lib/python2.7/threading.py", line 810, in
>>> __bootstrap_inner
>>> File "/usr/local/lib/python2.7/threading.py", line 763, in run
>>> File
>>> "/usr/local/lib/python2.7/site-packages/cassandra/io/asyncorereactor.py",
>>> line 52, in _run_loop
>>> : __exit__
>>>
>>>
>>> Can someone help me fixing this error?
>>>
>>> Regards,
>>> Sundeep
>>>
>>
>>
>
--
:- a)
Alex Popescu
Sen. Product Manager @ DataStax
@al3xandru
Re: Which hector version is suitable for cassandra 2.0.6 ?
On Thu, Mar 27, 2014 at 2:23 AM, user 01 wrote: > Btw both Hector & Datastax java driver are maintained by Datastax, & both > for java, this speaks for itself ! Hector is not maintained by DataStax. -- :- a) Alex Popescu Sen. Product Manager @ DataStax @al3xandru
Re: DataStax Devcenter CQL3 version vs Cassandra vrs
DevCenter 1.0 is the Java driver 1.0 to connect to your cluster. This version of the driver doesn't support C* 2.0 with its latest CQL version. Now you'll still be able to connect to a C* 2.0 cluster, but your queries will actually need to be compatible with C* 1.2 (basically none of the new CQL features will work). On the bright side, we're working on updating DevCenter to use the Java driver 2.0 which supports both C* 1.2 and 2.0 (and their corresponding CQL versions). On Fri, Mar 28, 2014 at 10:41 AM, Philip G wrote: > Within DevCenter, I'm getting an error: [feature] is introduced in CQL > 3.1.0, you're running CQL 3.0.5. > > This doesn't make sense as I'm using the absolute latest version of > Cassandra (2.0.6); connecting through cqlsh shows it's using 3.1.1: > > Connected to Test Cluster at localhost:9160. > [cqlsh 4.1.1 | Cassandra 2.0.6 | CQL spec 3.1.1 | Thrift protocol > 19.39.0] > Use HELP for help. > > What can I do to make DevCenter understand it should be connecting using > 3.1.1? > > --- > Philip > g...@gpcentre.net > http://www.gpcentre.net/ > -- :- a) Alex Popescu Sen. Product Manager @ DataStax @al3xandru
Re: DataStax .NET Driver - Converting from Row to DataRow
Arko, Please send your question to the .Net driver mailing list where you'll have better chances to get an answer: https://groups.google.com/a/lists.datastax.com/forum/#!forum/csharp-driver-user thanks On Wed, Feb 24, 2016 at 6:37 PM, Arko Provo Mukherjee < arkoprovomukher...@gmail.com> wrote: > Hello, > > I am trying to play with the Datastax .Net Driver for Cassandra. > > I understand that the .Fill() method is not implemented in CqlDataAdapter. > > Hence I was wondering if there is any elegant way to copy a Cassandra > Row to a DataRow? I can then construct a DataSet myself. > > Thanks & regards > Arko > -- Bests, Alex Popescu | @al3xandru Sen. Product Manager @ DataStax
Re: Exception about too long clustering key
Hi Emīls, Directing this question to the Java driver mailing list will give you better chances to get an answer: https://groups.google.com/a/lists.datastax.com/forum/#!forum/java-driver-user (as a side note, I haven't seen this one before) On Wed, Mar 9, 2016 at 11:52 AM, Emīls Šolmanis wrote: > Hello, > > I keep getting an exception about a clustering key being too long, like > > com.datastax.driver.core.exceptions.InvalidQueryException: The sum of all > clustering columns is too long (72650 > 65535) > at > com.datastax.driver.core.Responses$Error.asException(Responses.java:136) > at > com.datastax.driver.core.DefaultResultSetFuture.onSet(DefaultResultSetFuture.java:179) > at > com.datastax.driver.core.RequestHandler.setFinalResult(RequestHandler.java:184) > > > But the table has no clustering key. Even if I set the clustering key to a > single column that's guaranteed to be a string around 4-5 characters, I get > the same thing. > > The only result Google gave me suggested this was about the clustering key > names, so I renamed all the fields in the schema def to 1-3 letters, to no > avail. > > Does anyone know what this is about and how I can solve this? > > Running Cassandra 2.2.4, Datastax driver 3.0.0. > > Regards, > Emils > -- Bests, Alex Popescu | @al3xandru Sen. Product Manager @ DataStax
Re: com.datastax.driver.core.Connection "This should not happen and is likely a bug, please report."
Hi Thunder, This would be better sent to the Java mailing list https://groups.google.com/a/lists.datastax.com/forum/#!forum/java-driver-user. A quick search revealed https://datastax-oss.atlassian.net/browse/JAVA-603 which seem to match the Cassandra/DataStax community version but not the driver version. On Mon, Mar 21, 2016 at 9:33 PM, Thunder Stumpges < thunder.stump...@gmail.com> wrote: > Hi guys, > > So, quick background, we are using Outworkers (previously WebSudos) > Phantom v 1.22.0 Which appears to be using DataStax driver 3.0.0. We are > running scala 2.10 inside Samza on Yarn (CDH 5.4.4) with Oracle JDK 8. > > This is all pointing at a 3 node dev cluster of DataStax Community v 2.1.13 > > After running for a short time, the following error is thrown by the > Datastax driver in the Samza container: > > Logger: com.datastax.driver.core.Connection > Message: > "Forcing termination of Connection[/:9042-3, > inFlight=0, closed=true]. This should not happen and is likely a bug, > please report." > > There aren't really any other logs around this time, so not sure what else > I can provide. It said to "please report" so I guess I am. If what I have > provided is enough information to actually file a bug report, please let me > know and I will. Otherwise, what additional information can I collect for > this? > > Thanks, > Thunder > > -- Bests, Alex Popescu | @al3xandru Sen. Product Manager @ DataStax
Re: Production Ready/Stable DataStax Java Driver
Hi Anuj, All released versions of the DataStax Java driver are production ready: 1. they all go through the complete QA cycle 2. we merge all bug fixes and improvements upstream. Now, if you are asking which is currently the most deployed version, that's 2.1 (latest version 2.1.10.1 [1]). If you want to be ready for future Cassandra upgrades and benefit of the latest features of the Java driver, then that's the 3.0 branch (latest version 3.0.1 [2]). Last but not least, you should also consider when making the decision that our current focus and main development goes into the 3.x branch and that the 2.1 is in maintenance mode (meaning that no new features will be added and it will only see critical bug fixes). Bottom line, if your application is not already developed against the 2.1 version of the Java driver, you should use the latest 3.0 release. [1]: https://groups.google.com/a/lists.datastax.com/d/msg/java-driver-user/bYQSUvKQm5k/JduPTt7cGAAJ [2]: https://groups.google.com/a/lists.datastax.com/d/msg/java-driver-user/tOWZm4RVbm4/5E_aDAc8IAAJ On Sun, May 8, 2016 at 7:39 AM, Anuj Wadehra wrote: > Hi, > > Which DataStax Java Driver release is most stable (production ready) for > Cassandra 2.1? > > Thanks > Anuj > > > -- Bests, Alex Popescu | @al3xandru Sen. Product Manager @ DataStax <http://cassandrasummit.org/Email_Signature> » DataStax Enterprise - the database for cloud applications. «
Re: Production Ready/Stable DataStax Java Driver
On Sun, May 8, 2016 at 10:00 AM, Anuj Wadehra wrote: > As 3.x driver supports all 1.2+ Cassandra versions, I would also like to > better understand the motivation of having 2.1 releases simultaneously with > 3.x releases of Java driver. Hi Anuj, Both Apache Cassandra and the DataStax drivers are evolving fast with significant improvements across the board. While we support and provide the latest and greatest, we do also support the users that are already in production and allow them enough time to upgrade. Major release are sometimes introducing breaking changes. That's unfortunate but sometimes the only way we can push things forward. I do agree with your assessment 1000% that if starting now, the best version to go with is the latest on the 3.0 branch. -- Bests, Alex Popescu | @al3xandru Sen. Product Manager @ DataStax <http://cassandrasummit.org/Email_Signature> » DataStax Enterprise - the database for cloud applications. «
Re: Lattest driver and netty issues...
Tony, This thread will have much better chances to get answers and feedback if posted on the Java driver mailing list: https://groups.google.com/a/lists.datastax.com/forum/m/#!forum/java-driver-user On Thursday, May 26, 2016, Tony Anecito wrote: > Okay, think I understand the issue. Seems netty/casandra driver expect > the javax.security.cert.X509Certificate to be readily available which it is > for normal standalone java clients but it is not for the server side. That > class is in the rt.jar for the jre. But since the server side does not use > the rt.jar it is not found. Some recent change in netty or the datastax > driver expects the class but it can not be found on the server side. > > I hate to use the client side rt.jar with all the javax classes but that > is what is needed. I suspect the datastax testing did not take this into > account? I am using cassandra driver with the Wildfly J2EE container so I > am using the driver in that configuration not a standalone client. That by > the way worked fine when I was testing some CQL through the driver. > > Regards, > -Tony > > > On Wednesday, May 25, 2016 8:56 PM, Tony Anecito > wrote: > > > Ok I found the additional handler file and I added but at runtime I am > still getting the error message about the timer class not found and I > looked in the jar and did not see that class. I was using > netty-3.0.9.0.Final with Cassandra driver cassandra-driver-core-3.0.2.jar > and netty-handler-4.0.33.jar. > > So what is the right combination to not get this timer class missing > exception? > > Thanks. > > > On Wednesday, May 25, 2016 8:26 PM, Tony Anecito > wrote: > > > Hi All, > > I downloaded the latest cassandra driver but when used I get an error > about class io.netty.util.timer (netty-3.9.0.Final) not being found during > runtime. If I get the latest netty-alll-4.0.46.Final.jar during runtime I > get an exception about not having a java.security.cert.x509Certificate > class. > > So what to do? > > Thanks! > > > > > -- Bests, Alex Popescu | @al3xandru Sen. Product Manager @ DataStax <http://cassandrasummit.org/Email_Signature> » DataStax Enterprise - the database for cloud applications. «
Re: cassandra python driver routing requests to one node?
I'm wondering if what you are seeing is https://datastax-oss.atlassian.net/browse/PYTHON-643 (that could still be a sign of a potential data hotspot) On Sun, Nov 13, 2016 at 10:57 PM, Andrew Bialecki < andrew.biale...@klaviyo.com> wrote: > We're using the "default" TokenAwarePolicy. Our nodes are spread across > different racks within one datacenter. I've turned on debug logging for the > Python driver, but it doesn't look like it logs which Casandra node each > request goes to, but maybe I haven't got the right logging set to debug. > > On Mon, Nov 14, 2016 at 12:39 AM, Ben Slater > wrote: > >> What load balancing policies are you using in your client code ( >> https://datastax.github.io/python-driver/api/cassandra/policies.html)? >> >> Cheers >> Ben >> >> On Mon, 14 Nov 2016 at 16:22 Andrew Bialecki >> wrote: >> >>> We have an odd situation where all of a sudden of our cluster started >>> seeing a disproportionate number of writes go to one node. We're using the >>> Python driver version 3.7.1. I'm not sure if this is a driver issue or >>> possibly a network issue causing requests to get routed in an odd way. It's >>> not absolute, there are requests going to all nodes. >>> >>> Tried restarting the problematic node, no luck (those are the quiet >>> periods). Tried restarting the clients, also no luck. Checked nodetool >>> status and ownership is even across the cluster. >>> >>> Curious if anyone's seen this behavior before. Seems like the next step >>> will be to debug the client and see why it's choosing that node. >>> >>> [image: Inline image 1] >>> >>> >>> -- >>> AB >>> >> > > > -- > AB > -- Bests, Alex Popescu | @al3xandru Sen. Product Manager @ DataStax
Re: : Read a negative frame size (-2113929216)!
Can you share the relevant code snippet that leads to this exception? On Fri, Apr 25, 2014 at 4:47 PM, Vivek Mishra wrote: > datastax java driver 2.0.1 > > > > > On Sat, Apr 26, 2014 at 1:35 AM, Chris Lohfink > wrote: > >> what client are you using? >> >> On Apr 25, 2014, at 3:01 PM, Vivek Mishra wrote: >> >> It's a simple cql3 query to create keyspace. >> >> -Vivek >> >> >> On Sat, Apr 26, 2014 at 1:28 AM, Chris Lohfink >> wrote: >> >>> Did you send an enormous write or batch write and it wrapped? Or is >>> your client trying to use non-framed transport? >>> >>> Chris >>> >>> On Apr 25, 2014, at 2:50 PM, Vivek Mishra wrote: >>> >>> > This is what i am getting with Cassandra 2.0.7 with Thrift. >>> > >>> > >>> > Caused by: org.apache.thrift.transport.TTransportException: Read a >>> negative frame size (-2113929216)! >>> > at >>> org.apache.thrift.transport.TFramedTransport.readFrame(TFramedTransport.java:133) >>> > at >>> org.apache.thrift.transport.TFramedTransport.read(TFramedTransport.java:101) >>> > at >>> org.apache.thrift.transport.TTransport.readAll(TTransport.java:84) >>> > at >>> org.apache.thrift.protocol.TBinaryProtocol.readAll(TBinaryProtocol.java:362) >>> > at >>> org.apache.thrift.protocol.TBinaryProtocol.readI32(TBinaryProtocol.java:284) >>> > at >>> org.apache.thrift.protocol.TBinaryProtocol.readMessageBegin(TBinaryProtocol.java:191) >>> > at >>> org.apache.thrift.TServiceClient.receiveBase(TServiceClient.java:69) >>> > >>> > Any pointer/suggestions? >>> > >>> > -Vivek >>> >>> >> >> > -- :- a) Alex Popescu Sen. Product Manager @ DataStax @al3xandru
Re: Increased Cassandra connection latency
Also using the latest version of the driver (1.0.7) is always a good idea just to make sure you are not hitting issues that have already been addressed. On Thu, May 29, 2014 at 12:33 AM, Aaron Morton wrote: > You’ll need to provide some more information such as: > > * Do you have monitoring on the cassandra cluster that shows the request > latency ? Data Stax OpsCentre is good starting point. > > * Is compaction keeping up ? Check with nodetool compactionstats > > * Is the GCInspector logging about long running ParNew ? (it only logs > when it’s longer than 200ms) > > Cheers > Aaron > > > - > Aaron Morton > New Zealand > @aaronmorton > > Co-Founder & Principal Consultant > Apache Cassandra Consulting > http://www.thelastpickle.com > > On 23/05/2014, at 10:35 pm, Alexey Sverdelov < > alexey.sverde...@googlemail.com> wrote: > > Hi all, > > I've noticed increased latency on our tomcat REST-service (average 30ms, > max > 2sec). We are using Cassandra 1.2.16 with official DataStax Java > driver v1.0.3. > > Our setup: > > * 2 DCs > * each DC: 7 nodes > * RF=5 > * Leveled compaction > > After cassandra restart on all nodes, the latencies are alright again > (average < 5ms, max 50ms). > > Any thoughts are greatly appreciated. > > Thanks, > Alexey > > > -- :- a) Alex Popescu Sen. Product Manager @ DataStax @al3xandru
Re: python cql driver - cassandra.ReadTimeout - “Operation timed out - received only 1 responses.”
If I'm reading this correctly, what you are seeing is the read_timeout on
Cassandra side and not the client side timeout. Even if you set the client
side timeouts, the C* read & write timeouts are still respected on that
side.
On Mon, Jun 2, 2014 at 10:55 AM, Marcelo Elias Del Valle <
marc...@s1mbi0se.com.br> wrote:
> I am using Cassandra 2.0 with python CQL.
>
> I have created a column family as follows:
>
> CREATE KEYSPACE IF NOT EXISTS Identification
> WITH REPLICATION = { 'class' : 'NetworkTopologyStrategy',
> 'DC1' : 1 };
>
> USE Identification;
>
> CREATE TABLE IF NOT EXISTS entitylookup (
> name varchar,
> value varchar,
> entity_id uuid,
> PRIMARY KEY ((name, value), entity_id))
> WITH
> caching=all;
>
> I then try to count the number of records in this CF as follows:
>
> #!/usr/bin/env pythonimport argparseimport sysimport tracebackfrom cassandra
> import ConsistencyLevelfrom cassandra.cluster import Clusterfrom
> cassandra.query import SimpleStatement
> def count(host, cf):
> keyspace = "identification"
> cluster = Cluster([host], port=9042, control_connection_timeout=6)
> session = cluster.connect(keyspace)
> session.default_timeout=6
>
> st = SimpleStatement("SELECT count(*) FROM %s" % cf,
> consistency_level=ConsistencyLevel.ALL)
> for row in session.execute(st, timeout=6):
> print "count for cf %s = %s " % (cf, str(row))
> dump_pool.close()
> dump_pool.join()
> if __name__ == "__main__":
> parser = argparse.ArgumentParser()
> parser.add_argument("-cf", "--column-family", default="entitylookup",
> help="Column Family to query")
> parser.add_argument("-H", "--host", default="localhost", help="Cassandra
> host")
> args = parser.parse_args()
>
> count(args.host, args.column_family)
>
> print "fim"
>
> The count is not that useful to me, it's just a test with an operation
> that takes long to complete.
>
> Although I have defined timeout as 6 seconds, after less than 30
> seconds I get the following error:
>
> ./count_entity_lookup.py -H localhost -cf entitylookup
> Traceback (most recent call last):
> File "./count_entity_lookup.py", line 27, in
> count(args.host, args.column_family)
> File "./count_entity_lookup.py", line 16, in count
> for row in session.execute(st, timeout=None):
> File
> "/home/mvalle/pyenv0/local/lib/python2.7/site-packages/cassandra/cluster.py",
> line 1026, in execute
> result = future.result(timeout)
> File
> "/home/mvalle/pyenv0/local/lib/python2.7/site-packages/cassandra/cluster.py",
> line 2300, in result
> raise self._final_exception
> cassandra.ReadTimeout: code=1200 [Timeout during read request]
> message="Operation timed out - received only 1 responses."
> info={'received_responses': 1, 'data_retrieved': True, 'required_responses':
> 2, 'consistency': 5}
>
> It seems the answer was found in just a replica, but this really doesn't
> make sense to me. Should't cassandra be able to query it anyway?
>
> These tests are running in a two node cluster, with RF = 2, write and read
> consistency = ALL (but same results using QUORUM).
>
> Thanks in advance.
>
> Best regards,
>
> Marcelo.
>
--
:- a)
Alex Popescu
Sen. Product Manager @ DataStax
@al3xandru
Re: Cassandra connectors
On Fri, Jul 11, 2014 at 4:23 AM, Lohith Samaga wrote: > Questions: > 1. Do we have any jdbc driver for Cassandra 2.x series? If no, are tehre > any plans to build one? > There's no JDBC driver for C* 2.x, though we might create a wrapper over the Java driver at some point. It should be noted that due to the richer data types in C* there will be limitations with such a JDBC driver. > 2. Do we have a RESTful interface for Cassandra? > Accessing C* is done over the CQL protocol. Creating a RESTful API that is crafted for your application needs will deliver much better results than a generic interface. This would make things a lot more complicated on C* side and could potentially expose your data to security risks. -- :- a) Alex Popescu Sen. Product Manager @ DataStax @al3xandru
Re: [RELEASE] Apache Cassandra 2.1.0
Apologies for the late reply: the 2.1.x version of the C#, Java and Python DataStax drivers support the new Cassandra 2.1 version. Here's the quick list of links: C#: Latest version: 2.1.2 Nuget: https://www.nuget.org/packages/CassandraCSharpDriver/ Java: Latest version: 2.1.1 Maven: http://maven-repository.com/artifact/com.datastax.cassandra Binary distro: http://www.datastax.com/download#dl-datastax-drivers Python: Latest version: 2.1.1 PyPi: https://pypi.python.org/pypi/cassandra-driver On Thu, Sep 11, 2014 at 10:58 AM, Tony Anecito wrote: > Ok is it part of the release or needs to be downloaded from Datastax > somewhere. I am wondering about the java driver. > > Thanks! > -Tony > > > On Thursday, September 11, 2014 9:47 AM, abhinav chowdary < > abhinav.chowd...@gmail.com> wrote: > > > Yes its was released java driver 2.1 > On Sep 11, 2014 8:33 AM, "Tony Anecito" wrote: > > Congrads team I know you worked hard on it!! > > One question. Where can users get a java Datastax driver to support this > version? If so is it released? > > Best Regards, > -Tony Anecito > Founder/President > MyUniPortal LLC > http://www.myuniportal.com > > > On Thursday, September 11, 2014 9:05 AM, Sylvain Lebresne < > sylv...@datastax.com> wrote: > > > The Cassandra team is pleased to announce the release of the final version > of Apache Cassandra 2.1.0. > > Cassandra 2.1.0 brings a number of new features and improvements including > (but > not limited to): > - Improved support of Windows. > - A new incremental repair option[4, 5] > - A better row cache that can cache only the head of partitions[6] > - Off-heap memtables[7] > - Numerous performance improvements[8, 9] > - CQL improvements and additions: User-defined types, tuple types, 2ndary >indexing of collections, ...[10] > - An improved stress tool[11] > > Please refer to the release notes[1] and changelog[2] for details. > > Both source and binary distributions of Cassandra 2.1.0 can be downloaded > at: > > http://cassandra.apache.org/download/ > > As usual, a debian package is available from the project APT repository[3] > (you will need to use the 21x series). > > The Cassandra team > > [1]: http://goo.gl/k4eM39 (CHANGES.txt) > [2]: http://goo.gl/npCsro (NEWS.txt) > [3]: http://wiki.apache.org/cassandra/DebianPackaging > [4]: http://goo.gl/MjohJp > [5]: http://goo.gl/f8jSme > [6]: http://goo.gl/6TJPH6 > [7]: http://goo.gl/YT7znJ > [8]: http://goo.gl/Rg3tdA > [9]: http://goo.gl/JfDBGW > [10]: http://goo.gl/kQl7GW > [11]: http://goo.gl/OTNqiQ > > > > > > -- :- a) Alex Popescu Sen. Product Manager @ DataStax @al3xandru
Re: Named Parameters in Prepared Statement
Yes, you can bind parameters by name:
```
INSERT INTO songs (id, title, album, artist) VALUES (:id, :title, :album,
:artist)
```
All DataStax drivers for Cassandra support this feature. In Java it looks
like
// prepare only once
PreparedStatememt pstmt = session.prepare("INSERT INTO songs (id, title,
album, artist) VALUES (:id, :title, :album, :artist)")
// later
BoundStatement stmt = new BoundStatement(pstmt);
stmt.setLong("id", 1234);
stmt.setString("title", "Example title");
On Mon, Sep 22, 2014 at 4:41 AM, Timmy Turner wrote:
> Looking through the CQL 3.1 grammar in Cassandra, I found a "':' ident"
> alternative in the "value" rule (line 961).
>
> Is this for binding named parameters in prepared statements? Is this
> currently supported by any of the drivers or in Cassandra (2.1) itself?
>
> Looking at the docs and the current Java driver it doesn't seem that way.
>
--
:- a)
Alex Popescu
Sen. Product Manager @ DataStax
@al3xandru
Re: DevCenter and Cassandra 2.1
Hi Andrew, DevCenter has a complete CQL parser inside which helps with the offline validations and suggestions. So the bad news is that it requires a new version for every CQL grammar change. The good news is that this wait is not going to be too long (I cannot talk yet about a specific release date, but it's getting there). On Fri, Sep 26, 2014 at 2:13 AM, Andrew Cobley wrote: > Hi all, > > I notice that descanter 1.1.1doesn’t support User defined types (as far as > I can see). Is it just a matter of importing a template or will we need to > wait for full 2.1 support in descanter ? > > Andy > > > The University of Dundee is a registered Scottish Charity, No: SC015096 > -- :- a) Alex Popescu Sen. Product Manager @ DataStax @al3xandru
Re: Working with legacy data via CQL
On Tuesday, November 11, 2014, Erik Forsberg wrote: > Hi! > > I have some data in a table created using thrift. In cassandra-cli, the > 'show schema' output for this table is: > > > Now, when I try to extract data from this using cqlsh or the > python-driver, I have no problems getting data for the columns which are > actually UTF8,but for those where column_metadata have been set to > something else, there's trouble. Example using the python driver: > > > For sure this is an ugly table, but I have data in it, and I would like > to avoid having to rewrite all my tools at once, so if I could support > it from CQL that would be great. > > Regards, > \EF > You'll have better chances to get an answer about the Python driver on its own mailing list https://groups.google.com/a/lists.datastax.com/forum/#!forum/python-driver-user -- [:>-a) Alex Popescu Sen. Product Manager @ DataStax @al3xandru
Re: Programmatic Cassandra version detection/extraction
On Wed, Nov 12, 2014 at 2:44 PM, Otis Gospodnetic < otis.gospodne...@gmail.com> wrote: > Hi, > > Is there a way to detect which version of Cassandra one is running? > Is there an API for that, or a constant with this value, or maybe an MBean > or some other way to get to this info? > > Here's the use case: > SPM monitors Cassandra <http://sematext.com/spm/>, but Cassandra MBeans > and metrics have or may change over time. > How will SPM agent know which MBeans to look for, which metrics to > extract, and how to interpret values it extracts without knowing which > version of Cassandra it's monitoring? > It could try probing for some known MBeans and deduce Cassandra version > from that, but that feels a little sloppy. > Ideally, we'd be able to grab the version from some MBean and based on > that extract metrics we know are exposed in that version of Cassandra. > > Thanks, > Otis > If you are using the Java driver, you can retrieve the version of Cassandra for each Host: http://www.datastax.com/drivers/java/2.1/com/datastax/driver/core/Host.html#getCassandraVersion() > -- > Monitoring * Alerting * Anomaly Detection * Centralized Log Management > Solr & Elasticsearch Support * http://sematext.com/ > > -- [:>-a) Alex Popescu Sen. Product Manager @ DataStax @al3xandru
Re: Datastax Cassandra Java Driver executeAsynch question.
Hi Bogdan, This question would be better on the specific driver's mailing list. Assuming you are using the Java driver the mailing list is [1]. As for your question look into PoolingOptions [2] that you pass when configuring the Cluster instance. [1]: https://groups.google.com/a/lists.datastax.com/forum/#!forum/java-driver-user [2]: http://www.datastax.com/drivers/java/2.1/com/datastax/driver/core/PoolingOptions.html On Mon, Jan 12, 2015 at 9:58 AM, Batranut Bogdan wrote: > Hello all, > > > In my implementation of the FutureCallBack<> interface in the onSuccess > method, I put Thread.currentThread.getName(). What I saw was that there is > a ThreadPool... That is all fine, but seems to me that the pool does not > have that many threads. About 10 from my observations - I did not bother to > get the exact number. Why? Well because when I query cassandra I have a > list of about 6000 cf keys. I traverse the list and executeAsynch a > prepared statement for each of these. I have seen that during the execution > the driver is waiting for free threads to continue if all the threads in > the pool are waiting for response from C*. > > How can I increase the number of threads that the driver uses to query > Cassandra? > > > -- [:>-a) Alex Popescu Sen. Product Manager @ DataStax @al3xandru
Re: UDF and DevCenter
Thanks for the feedback Andy. I'll forward this to the DevCenter team.
Currently we have an email for sending feedback our way:
devcenter-feedb...@datastax.com. And the good news is that in the next
release there will be an integrated feedback form directly in DevCenter.
On Thu, Jan 22, 2015 at 8:15 AM, Andrew Cobley (Staff) <
a.e.cob...@dundee.ac.uk> wrote:
>
> I’m not sure where to send “faults” for the DataStax Devcenter so I’ll
> send them here. If I define a UDT such as:
>
> CREATE TYPE if not exists sensorsync.SensorReading (
>
> fValue float,
> sValue text,
> iValue int
> );
>
> and a table
>
> Create table if not exists sensorsync.Sensors(
> name uuid,
> insertion_time timestamp,
> reading map >,
> Primary Key (name,insertion_time)
> )
>
> If I now want to insert data but not use all the fields in the UDT
> DevCenter flags it as a fault. So:
>
> insert into sensorsync.Sensors (name,insertion_time,reading) values (
> 7500e917-04b0-4697-ae7e-dbcdbf7415cb,'2015-01-01 02:10:05',{'sensor':{
> iValue:101},'sensor1':{fValue:30.5}});
>
> Works ok (rund in devcenter and cqlsh) but dev centre flags the missing
> values with an error. Minor, but may throw people a curve.
>
> Andy
>
>
>
> The University of Dundee is a registered Scottish Charity, No: SC015096
>
--
[:>-a)
Alex Popescu
Sen. Product Manager @ DataStax
@al3xandru
Re: Problems with user defined types (cql) and Datastax Java Driver
Andreas,
Can you please post your question to the Java driver ml
https://groups.google.com/a/lists.datastax.com/forum/#!forum/java-driver-user
as you'll have better chances to get an answer there.
thanks
On Thu, Feb 5, 2015 at 9:10 AM, Andreas Finke
wrote:
> Hi,
>
>
>
> I encountered the problem that in Java the Session does not create a valid
> UserType for my corresponding CQL user defined type.
>
>
>
> CQL_SCHEMA:
>
>
>
> create keyspace if not exists quotes
>
> WITH replication = { 'class' : 'SimpleStrategy', 'replication_factor' : 1
> };
>
>
>
> CREATE TYPE IF NOT EXISTS quotes.price (
>
> value double,
>
> size bigint,
>
> timestamp bigint,
>
> delay int
>
> );
>
>
>
> JAVA
>
>
>
> UserType priceType =
> session.getCluster().getMetadata().getKeyspace("quotes").getUserType("price");
>
> Assert.assertNotNull(priceType); // true
>
> Assert.assertEquals("price", priceType.getTypeName()); // true
>
> Assert.assertEquals(4, priceType.getFieldNames().size()); //
> AssertionFailedError: expected:<4> but was:<0>
>
>
>
> I am testing with Cassandra v.2.1.2 on Windows using Datastax Java Driver
> 2.1.2.
>
>
>
> I am thankful for any suggestions.
>
>
>
> Regards
>
> Andi
>
--
[:>-a)
Alex Popescu
Sen. Product Manager @ DataStax
@al3xandru
Re: about "insert into table with IF NOT EXISTS" error
Tom, this question would have better chances to be answered on the Node.js driver mailing list https://groups.google.com/a/lists.datastax.com/forum/#!forum/nodejs-driver-user On Mon, Feb 9, 2015 at 5:38 PM, tom wrote: > Hi: > > I setup one node cassandra server, and using node.js driver cql to query > db. > > But, when insert into table with "IF NOT EXISTS" statement, it report > error as below: > > :ResponseError: Cannot achieve consistency level QUORUM > > And, I try set nodejs cql query with consistency to ONE, still see that > error. > > If I remove "IF NOT EXISTS" from cql, insert passed. > > Please advice. thx. > > best regards > Tom > -- [:>-a) Alex Popescu Sen. Product Manager @ DataStax @al3xandru
Re: Pagination support on Java Driver Query API
On Tue, Feb 10, 2015 at 4:59 AM, Ajay wrote: > 1) Java driver implicitly support Pagination in the ResultSet (using > Iterator) which can be controlled through FetchSize. But it is limited in a > way that we cannot skip or go previous. The FetchState is not exposed. Cassandra doesn't support skipping so this is not really a limitation of the driver. -- [:>-a) Alex Popescu Sen. Product Manager @ DataStax @al3xandru
Re: Connecting to Cassandra cluster in AWS from local network
You'll have to configure your nodes to:
1. use AWS internal IPs for inter-node connection (check listen_address)
and
2. use the AWS public IP for client-to-node connections (check rpc_address)
Depending on the setup, there might be other interesting conf options in
cassandra.yaml (broadcast_address, listen_interface, rpc_interface).
[1]:
http://docs.datastax.com/en/cassandra/2.1/cassandra/configuration/configCassandra_yaml_r.html
On Mon, Apr 20, 2015 at 9:50 AM, Jonathan Haddad wrote:
> Ideally you'll be on the same network, but if you can't be, you'll need to
> use the public ip in listen_address.
>
> On Mon, Apr 20, 2015 at 9:47 AM Matthew Johnson
> wrote:
>
>> Hi all,
>>
>>
>>
>> I have set up a Cassandra cluster with 2.1.4 on some existing AWS boxes,
>> just as a POC. Cassandra servers connect to each other over their internal
>> AWS IP addresses (172.x.x.x) aliased in /etc/hosts as sales1, sales2 and
>> sales3.
>>
>>
>>
>> I connect to it from my local dev environment using the seed’s external
>> NAT address (54.x.x.x) aliases in my Windows hosts file as sales3 (my seed).
>>
>>
>>
>> When I try to connect, it connects fine, and can retrieve some data (I
>> have very limited amounts of data in there, but it seems to retrieve ok),
>> but I also get lots of stacktraces in my log where my dev environment is
>> trying to connect to Cassandra on the internal IP (presumably the Cassandra
>> seed node tells my dev env where to look):
>>
>>
>>
>>
>>
>> *INFO 2015-04-20 16:34:14,808 [CASSANDRA-CLIENT] {main} Cluster - New
>> Cassandra host sales3/54.x.x.142:9042 added*
>>
>> *INFO 2015-04-20 16:34:14,808 [CASSANDRA-CLIENT] {main} Cluster - New
>> Cassandra host /172.x.x.237:9042 added*
>>
>> *INFO 2015-04-20 16:34:14,808 [CASSANDRA-CLIENT] {main} Cluster - New
>> Cassandra host /172.x.x.170:9042 added*
>>
>> *Connected to cluster: Test Cluster*
>>
>> *Datatacenter: datacenter1; Host: /172.x.x.170; Rack: rack1*
>>
>> *Datatacenter: datacenter1; Host: sales3/54.x.x.142; Rack: rack1*
>>
>> *Datatacenter: datacenter1; Host: /172.x.x.237; Rack: rack1*
>>
>> *DEBUG 2015-04-20 16:34:14,901 [CASSANDRA-CLIENT] {Cassandra Java Driver
>> worker-0} Connection - Connection[sales3/54.x.x.142:9042-2, inFlight=0,
>> closed=false] Transport initialized and ready*
>>
>> *DEBUG 2015-04-20 16:34:14,901 [CASSANDRA-CLIENT] {Cassandra Java Driver
>> worker-0} Session - Added connection pool for sales3/54.x.x.142:9042*
>>
>> *DEBUG 2015-04-20 16:34:19,850 [CASSANDRA-CLIENT] {Cassandra Java Driver
>> worker-1} Connection - Connection[/172.x.x.237:9042-1, inFlight=0,
>> closed=false] Error connecting to /172.x.x.237:9042 (connection timed out:
>> /172.x.x.237:9042)*
>>
>> *DEBUG 2015-04-20 16:34:19,850 [CASSANDRA-CLIENT] {Cassandra Java Driver
>> worker-1} Connection - Defuncting connection to /172.x.x.237:9042*
>>
>> *com.datastax.driver.core.TransportException**: [/172.x.x.237:9042]
>> Cannot connect*
>>
>>
>>
>>
>>
>> Does anyone have any experience with connecting to AWS clusters from dev
>> machines? How have you set up your aliases to get around this issue?
>>
>>
>>
>> Current setup in sales3 (seed node) cassandra.yaml:
>>
>>
>>
>> *- seeds: "sales3"*
>>
>> *listen_address: sales3*
>>
>> *rpc_address: sales3*
>>
>>
>>
>> Current setup in other nodes (eg sales2) cassandra.yaml:
>>
>>
>>
>> *- seeds: "sales3"*
>>
>> *listen_address: sales2*
>>
>> *rpc_address: sales2*
>>
>>
>>
>>
>>
>> Thanks!
>>
>> Matt
>>
>>
>>
>
--
Bests,
Alex Popescu | @al3xandru
Sen. Product Manager @ DataStax
Re: Creating 'Put' requests
On Thu, Apr 23, 2015 at 8:50 AM, Matthew Johnson wrote: > Unfortunately it seems that I was misinformed on the “dynamically creating > timeseries columns” feature, and that this WAS deprecated in CQL3 – in > order to dynamically create columns I would have to issue an ‘ALTER TABLE’ > statement for every new column. I read one suggestions which is to use > collections instead - so basically have a single pre-defined column which > is a Map, say, and then add ‘timestamp : value’ into that map instead of a > new column for every timestamp. Would you say this is an acceptable > approach? Depending on the data model and the queries your application will use, you'll be using either clustering columns or collections (or a combination). If you need help modeling, you could start a new thread with the relevant details and I'm pretty sure you'll get some good suggestions here. -- Bests, Alex Popescu | @al3xandru Sen. Product Manager @ DataStax
Re: cassandra installation
The JVM is the runtime platform for Cassandra. You can use any driver with it (there's no default driver). DataStax provides quite a few open source drivers [1] and there are also community maintained drivers [2] [1]: https://github.com/datastax/ [2]: http://planetcassandra.org/client-drivers-tools/ On Tue, Jun 9, 2015 at 8:26 AM, ICHIBA Sara wrote: > hey there, > > In order to install cassandra, java has to be installed first. is that > mean that the default driver of cassandra is java? what if we wanna use the > cpp driver? > > P.S 1: my questions might be so dump, but I will really appreciate an > answer. > PS 2: I'm intern and i'm completely new to cassandra so... > > -- Bests, Alex Popescu | @al3xandru Sen. Product Manager @ DataStax
Re: no file cassandra.h found
Please send this question to the DataStax C++ mailing list https://groups.google.com/a/lists.datastax.com/forum/#!forum/cpp-driver-user On Thu, Jun 11, 2015 at 8:57 AM, ICHIBA Sara wrote: > hey there, > > I'm trying to compile a script which include the line #include > . the compilation is never completed and I have the error > file/directory cassandra.h not found. Any idea how to fix this knowing that > I have the Datastax Cassandra cpp-driver installed?? > > In advance, thank you for your response, > Sara > -- Bests, Alex Popescu | @al3xandru Sen. Product Manager @ DataStax
Re: Using Cassandra and Twisted (Python)
Jonathan, I'm pretty sure you'll have better chances to get this answered on the Python driver mailing list https://groups.google.com/a/lists.datastax.com/forum/#!forum/python-driver-user On Tue, Jun 16, 2015 at 1:01 AM, Jonathan Ballet wrote: > Hi, > > I'd like to write some Python applications using Twisted to talk to a > Cassandra cluster. > > It seems like the Datastax Python library from > https://github.com/datastax/python-driver does support Twisted, but it's > not exactly clear how I would use this library along with Twisted. The > documentation for the async API is very sparse and there's no mention on > how to plug this into Twisted event-loop. > > Does anyone have a small working example on how to use both of these? > > Thanks! > > Jonathan > -- Bests, Alex Popescu | @al3xandru Sen. Product Manager @ DataStax
Re: Any use-case about a migration from SQL Server to Cassandra?
On Tue, Jun 23, 2015 at 12:13 PM, Marcos Ortiz wrote: > 2- They used heavily C# in a Microsoft-based environment, so I need to > know if the .Net driver is ready to use for production The DataStax C# driver has been used in production for quite a while by numerous users. It is the most up-to-date, feature rich, and tunable C# driver for Apache Cassandra and DataStax Enterprise. Anyways, if there's anything missing we are always happy to improve it. (as you can see from my sig, I do work for DataStax, but the above is very true) -- Bests, Alex Popescu | @al3xandru Sen. Product Manager @ DataStax
Re: DevCenter 1.2.0 keep failing in KDE 4.14.1
Hi Marcos, On Tue, Jun 23, 2015 at 12:23 PM, Marcos Ortiz wrote: > MaxPermSize=256m; support was removed in 8.0 1. The MaxPermSize is just a warning. 2. This is the first time I've seen that error. Search revealed this StackOverflow thread http://stackoverflow.com/questions/26436009/eclipse-luna-crashes-on-new-project-in-ubuntu which mentions a workaround. 3. Last but definitely the most important, I'd strongly encourage you to upgrade to the latest version of DevCenter 1.3.1 http://www.datastax.com/download-ops-dev#DataStax_DevCenter -- Bests, Alex Popescu | @al3xandru Sen. Product Manager @ DataStax
Re: [MASSMAIL]Re: DevCenter 1.2.0 keep failing in KDE 4.14.1
On Tue, Jun 23, 2015 at 12:58 PM, Marcos Ortiz wrote: > OK, I will do it. As a side note, DevCenter 1.3 also has supported for reaching out to us directly [1] http://www.datastax.com/dev/blog/devcenter-1-3-available-now-featuring-schema-wizards-and-execution-of-highlighted-statements -- Bests, Alex Popescu | @al3xandru Sen. Product Manager @ DataStax
Re: date type and SimpleDateSerializer for Cassandra-2.2.0
;at io.netty.handler.codec.ByteToMessageDecoder.channelRead( > *ByteToMessageDecoder.java:244*) > >at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead( > *AbstractChannelHandlerContext.java:308*) > >at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead( > *AbstractChannelHandlerContext.java:294*) > >at io.netty.channel.DefaultChannelPipeline.fireChannelRead( > *DefaultChannelPipeline.java:846*) > >at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read( > *AbstractNioByteChannel.java:131*) > >at io.netty.channel.nio.NioEventLoop.processSelectedKey( > *NioEventLoop.java:511*) > >at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized( > *NioEventLoop.java:468*) > >at io.netty.channel.nio.NioEventLoop.processSelectedKeys( > *NioEventLoop.java:382*) > >at io.netty.channel.nio.NioEventLoop.run(*NioEventLoop.java:354*) > >... 2 more > > > > What Am I doing wrong? > > > > Thank you for your help. > > > > Regards > > > > Philippe SURAY > -- Bests, Alex Popescu | @al3xandru Sen. Product Manager @ DataStax <http://cassandrasummit-datastax.com/?utm_campaign=summit15&utm_medium=summiticon&utm_source=emailsignature>
Re: memory usage problem of Metadata.tokenMap.tokenToHost
Besides the others' advice that 2000+ keyspaces might be too much, the latest Java driver (2.0.11) includes an option to disable the Metadata API http://www.datastax.com/dev/blog/datastax-java-driver-2-0-11-released. I'm not sure at this moment if this has been merged into 2.1 already. On Sun, Sep 20, 2015 at 9:22 AM, joseph gao wrote: > cassandra: 2.1.7 > java driver: datastax java driver 2.1.6 > > Here is the problem: >My application uses 2000+ keyspaces, and will dynamically create > keyspaces and tables. And then in java client, the > Metadata.tokenMap.tokenToHost would use about 1g memory. so this will cause > a lot of full gc. >As I see, the key of the tokenToHost is keyspace, and the value is a > tokenId_to_replicateNodes map. > >When I try to solve this problem, I find something not sure: all > keyspaces have same 'tokenId_to_replicateNodes' map. > My replication strategy of all keyspaces is : simpleStrategy and > replicationFactor is 3 > > So would it be possible if keyspaces use same strategy, the value of > tokenToHost map use a same map. So it would extremely reduce the memory > usage > > thanks a lot > > -- > -- > Joseph Gao > PhoneNum:15210513582 > QQ: 409343351 > -- Bests, Alex Popescu | @al3xandru Sen. Product Manager @ DataStax <http://cassandrasummit-datastax.com/?utm_campaign=summit15&utm_medium=summiticon&utm_source=emailsignature>
Re: cassandra 3.0 rc1 and datastax java driver 3.0.0 alpha3
You'll have better chances to get an answer directly on the Java driver mailing list: https://groups.google.com/a/lists.datastax.com/forum/#!forum/java-driver-user thanks On Sat, Oct 10, 2015 at 4:30 PM, Vova Shelgunov wrote: > Hi all, > > I've tried to connect to the cassandra 3.0 cluster, using datastax java > driver, but I got the following exception when I tried to craete > MappingManager: > > Caused by: com.datastax.driver.core.exceptions.CodecNotFoundException: > Codec not found for requested operation: > [varchar <-> V] > at > com.datastax.driver.core.CodecRegistry.newException(CodecRegistry.java:647) > at > com.datastax.driver.core.CodecRegistry.createCodec(CodecRegistry.java:499) > at > com.datastax.driver.core.CodecRegistry.findCodec(CodecRegistry.java:481) > at > com.datastax.driver.core.CodecRegistry.maybeCreateCodec(CodecRegistry.java:554) > at > com.datastax.driver.core.CodecRegistry.createCodec(CodecRegistry.java:497) > at > com.datastax.driver.core.CodecRegistry.findCodec(CodecRegistry.java:481) > at > com.datastax.driver.core.CodecRegistry.access$400(CodecRegistry.java:143) > at > com.datastax.driver.core.CodecRegistry$1.load(CodecRegistry.java:295) > at > com.datastax.driver.core.CodecRegistry$1.load(CodecRegistry.java:293) > at > com.google.common.cache.LocalCache$LoadingValueReference.loadFuture(LocalCache.java:3522) > at > com.google.common.cache.LocalCache$Segment.loadSync(LocalCache.java:2315) > at > com.google.common.cache.LocalCache$Segment.lockedGetOrLoad(LocalCache.java:2278) > at > com.google.common.cache.LocalCache$Segment.get(LocalCache.java:2193) > at com.google.common.cache.LocalCache.get(LocalCache.java:3932) > at > com.google.common.cache.LocalCache.getOrLoad(LocalCache.java:3936) > at > com.google.common.cache.LocalCache$LocalLoadingCache.get(LocalCache.java:4806) > at > com.datastax.driver.core.CodecRegistry.lookupCodec(CodecRegistry.java:457) > at > com.datastax.driver.core.CodecRegistry.codecFor(CodecRegistry.java:426) > at > com.datastax.driver.core.AbstractGettableByIndexData.codecFor(AbstractGettableByIndexData.java:89) > at > com.datastax.driver.core.AbstractGettableByIndexData.getMap(AbstractGettableByIndexData.java:390) > at > com.datastax.driver.core.AbstractGettableData.getMap(AbstractGettableData.java:26) > at > com.datastax.driver.core.AbstractGettableByIndexData.getMap(AbstractGettableByIndexData.java:378) > at > com.datastax.driver.core.AbstractGettableData.getMap(AbstractGettableData.java:26) > at > com.datastax.driver.core.AbstractGettableData.getMap(AbstractGettableData.java:233) > at > com.datastax.driver.core.KeyspaceMetadata.build(KeyspaceMetadata.java:70) > at > com.datastax.driver.core.SchemaParser.buildKeyspaces(SchemaParser.java:116) > at > com.datastax.driver.core.SchemaParser.refresh(SchemaParser.java:61) > at > com.datastax.driver.core.ControlConnection.refreshSchema(ControlConnection.java:328) > at > com.datastax.driver.core.ControlConnection.tryConnect(ControlConnection.java:258) > at > com.datastax.driver.core.ControlConnection.reconnectInternal(ControlConnection.java:185) > at > com.datastax.driver.core.ControlConnection.connect(ControlConnection.java:77) > at com.datastax.driver.core.Cluster$Manager.init(Cluster.java:1372) > at com.datastax.driver.core.Cluster.init(Cluster.java:160) > at > com.datastax.driver.core.SessionManager.initAsync(SessionManager.java:75) > at > com.datastax.driver.core.SessionManager.init(SessionManager.java:67) > at > com.datastax.driver.mapping.MappingManager.getProtocolVersion(MappingManager.java:65) > at > com.datastax.driver.mapping.MappingManager.(MappingManager.java:56) > > Could you please say what does it mean? > -- Bests, Alex Popescu | @al3xandru Sen. Product Manager @ DataStax
Re: Getting code=2200 [Invalid query] message=Invalid column name ... while executing ALTER statement
sqlAlterStatement1 = " ALTER TABLE test.iau ADD "+colName+" >>> text" >>> print sqlAlterStatement1 >>> session.execute(sqlAlterStatement1) >>> sqlAlterStatement1 = None >>> >>> print " Altered tables :: " >>> # >>> count = 0 >>> for colName in colNames : >>> count = count +1 >>> sqlUpdateGeneDetection = " UPDATE test.iau SET "+colName+" = >>> '"+str(count)+"' WHERE sample_id = 'sample123'" >>> session.execute(sqlUpdateGeneDetection) >>> sqlUpdateGeneDetection = None >>> >>> print " Updated tables :: " >>> session.cluster.shutdown() >>> >>> >>> #--- >>> >>> Very rarely this code works, but most of the time it fails when it reach >>> ALTER statement. >>> FYI, I tried preparedstatement with binding in INSERT, UPDATE statements >>> too. >>> >>> The error with output is shown here: >>> >>> #-- >>> created the table >>> >>> Inserted main ids into the table >>> ALTER TABLE test.iau ADD col1 text >>> ALTER TABLE test.iau ADD col2 text >>> ALTER TABLE test.iau ADD col3 text >>> ALTER TABLE test.iau ADD col4 text >>> ALTER TABLE test.iau ADD col5 text >>> ALTER TABLE test.iau ADD col6 text >>> ALTER TABLE test.iau ADD col7 text >>> ALTER TABLE test.iau ADD col8 text >>> ALTER TABLE test.iau ADD col9 text >>> E >>> == >>> >>> -- >>> Traceback (most recent call last): >>> File "UnitTests.py", line 313, in test_insert_data >>> session.execute(sqlAlterStatement1) >>> File "/usr/local/lib/python2.7/site-packages/cassandra/cluster.py", >>> line 1405, in execute >>> result = future.result(timeout) >>> File "/usr/local/lib/python2.7/site-packages/cassandra/cluster.py", >>> line 2976, in result >>> raise self._final_exception >>> InvalidRequest: code=2200 [Invalid query] message="Invalid column name >>> col9 because it conflicts with an existing column" >>> >>> -- >>> Ran 1 test in 9.856s >>> #-- >>> >>> But when I checked the table using CQL col9 is not there. >>> >>> Is there' schema' refresh issue or is it bug in Cassandra 2.1.5? >>> >>> Thank you. >>> Kind regards >>> Rajesh R >>> >>> >>> >>> >>> ** >>> The information contained in the EMail and any attachments is >>> confidential and intended solely and for the attention and use of the named >>> addressee(s). It may not be disclosed to any other person without the >>> express authority of Public Health England, or the intended recipient, or >>> both. If you are not the intended recipient, you must not disclose, copy, >>> distribute or retain this message or any part of it. This footnote also >>> confirms that this EMail has been swept for computer viruses by >>> Symantec.Cloud, but please re-sweep any attachments before opening or >>> saving. http://www.gov.uk/PHE >>> >>> ** >>> >> >> >> ** >> The information contained in the EMail and any attachments is >> confidential and intended solely and for the attention and use of the named >> addressee(s). It may not be disclosed to any other person without the >> express authority of Public Health England, or the intended recipient, or >> both. If you are not the intended recipient, you must not disclose, copy, >> distribute or retain this message or any part of it. This footnote also >> confirms that this EMail has been swept for computer viruses by >> Symantec.Cloud, but please re-sweep any attachments before opening or >> saving. http://www.gov.uk/PHE >> ** >> > > > ** > The information contained in the EMail and any attachments is confidential > and intended solely and for the attention and use of the named > addressee(s). It may not be disclosed to any other person without the > express authority of Public Health England, or the intended recipient, or > both. If you are not the intended recipient, you must not disclose, copy, > distribute or retain this message or any part of it. This footnote also > confirms that this EMail has been swept for computer viruses by > Symantec.Cloud, but please re-sweep any attachments before opening or > saving. http://www.gov.uk/PHE > ** > -- Bests, Alex Popescu | @al3xandru Sen. Product Manager @ DataStax
Re: Cassandra 3.0.0 connection problem
Hi Enrico, As Tyler mentioned, Cassandra 3.0 introduced some major changes to the system tables, which are critical to the way DataStax drivers work, that prevented drivers to connect. We are addressing these changes as fast as we can, but for the PHP driver we need to firstly update the underlying C/C++ driver and this is already being worked on. I don't have yet a time-frame to share though, but we know how important it is to have these out as soon as possible. Thanks for your understanding On Friday, November 20, 2015, Enrico Sola wrote: > I've seen now that the DataStax PHP driver (version 1.0.0, the only > available on github) it's only partially compatible with Cassandra 2.1, I > used it until 2.2.3, in fact in this one I can't use useful data type like > FROZEN or TUPLE. > On the DataStax developer blog that talk about a new beta version but > nothing has been released yet, I don't know why PHP driver has not been > updated with these latest Cassandra updates, I hope for a quick new release > for 3.0.0. > About downgrade unfortunately I forget about snapshot so I exported in > another way and after that completely uninstalled and installed again. > Thanks for informations! > > Enrico > > > Il giorno 19 nov 2015, alle ore 19:10, Tyler Hobbs > ha scritto: > > > On Thu, Nov 19, 2015 at 1:13 AM, Enrico Sola > wrote: > >> Hi, I'm new to Cassandra and I've recently upgraded to 3.0.0 on Ubuntu >> Linux 14.04 LTS, through apt-get upgrade not manual installation, after the >> update all was fine so I could access to my keyspaces using cqlsh but I >> can't access to Cassandra using DataStax PHP Driver because I get this >> error: "No hosts available for the control connection”. >> The connection parameters are the same of 2.2.3 version (and was working >> fine). >> I don't know if is this a bug or a problem of the PHP driver but my >> systems use Cassandra and are now offline, so it's a known issue with a >> solution? >> > > I don't think the PHP driver supports Cassandra 3.0 yet. There were some > changes to the system schema tables that are probably preventing it from > connecting successfully. > > >> I tried also to downgrade to 2.2.3 version but after that Cassandra >> didn't start due to keyspace loading problem, I'm just looking for a quick >> solution so doesn't matter if I have to downgrade to 2.2.3, so how can I do >> the downgrade without lose my datas? >> > > Downgrading major versions isn't supported, which is why we recommend that > you take a snapshot before upgrading. Your only real option for > downgrading without data loss is to dump your data (using cqlsh's COPY TO > or something similar) and then re-load it on 2.2 (using cqlsh's COPY FROM > or something similar). > > > -- > Tyler Hobbs > DataStax <http://datastax.com/> > > > -- Bests, Alex Popescu | @al3xandru Sen. Product Manager @ DataStax
Re: OpsCenter doen not work with Cassandra 3.0
Hi Sergey,
There were some changes of the system schema tables in the released version
of Cassandra 3.0 that are preventing tools like OpsCenter and DevCenter to
connect. We are working on releasing updated versions that are fully
compatible with C 3.0.
thanks for your understanding,
On Wed, Nov 25, 2015 at 3:45 PM, Sergey Panov wrote:
> Hello,
>
> Today we tried to setup DataStaxOpsCenter-5.2.2.2015102711-linux-x64 to
> work with Cassandra 3.0.
>
> OpsCenter logs have the following:
>
> 2015-11-26 02:17:39+0300 [] INFO: Starting factory
> 0x2521b00>
> 2015-11-26 02:17:40+0300 [] INFO: Stopping factory
> 0x2521b00>
> 2015-11-26 02:17:40+0300 [] WARN: [control connection] Error connecting to
> 172.20.30.91: Unexpected response during Connection setup:
> ProtocolError('Server pr
> otocol version (4) does not match the specified driver protocol version
> (2). Consider setting Cluster.protocol_version to 4.',)
> 2015-11-26 02:17:40+0300 [] ERROR: Control connection failed to connect,
> shutting down Cluster: ('Unable to connect to any servers',
> {u'172.20.30.91': Protocol
> Error("Unexpected response during Connection setup: ProtocolError('Server
> protocol version (4) does not match the specified driver protocol version
> (2). Consid
> er setting Cluster.protocol_version to 4.',)",)})
> 2015-11-26 02:17:40+0300 [] WARN: ProcessingError while calling
> CreateClusterConfController: Unable to connect to cluster. Error is: Unable
> to connect to any
> seed nodes, tried [u'172.20.30.91']
>
>
> How can we switch to protocol_version to 4?
> Does OpsCenter officially support the latest version of Cassandra?
> Did anybody try to setup it?
>
> Please advice. Thank you!
>
> --
>
> Sergey Panov
>
>
--
Bests,
Alex Popescu | @al3xandru
Sen. Product Manager @ DataStax
Re: memory usage problem of Metadata.tokenMap.tokenToHost
There are still a couple of tickets being worked on for 2.1.10 and the release will come afterwards. You can check the list: https://datastax-oss.atlassian.net/browse/JAVA-989?jql=project%20%3D%20JAVA%20AND%20fixVersion%20%3D%202.1.10 On Mon, Jan 4, 2016 at 5:57 AM, joseph gao wrote: > By the way, when would be the version 2.1.10 published? > > 2015-12-15 10:02 GMT+08:00 joseph gao : > >> That's great. Thanks, Alex! >> >> 2015-10-02 0:36 GMT+08:00 Alexandre Dutra : >> >>> I confirm that the optional schema metadata feature (JAVA-828 >>> <https://datastax-oss.atlassian.net/browse/JAVA-828>) has been merged >>> upstream and is included in driver 3.0.0-alpha3 and will as well be >>> included in the forthcoming 2.1.8 version. >>> >>> On a side note, JAVA-664 >>> <https://datastax-oss.atlassian.net/browse/JAVA-664> has been open for >>> quite a while now and aims to fix the problem you describe. It will >>> hopefully make it into 2.1.8 as well, although I cannot guarantee that at >>> this point. >>> >>> Thanks, >>> >>> Alexandre Dutra >>> >>> On Mon, Sep 28, 2015 at 7:55 PM Alex Popescu wrote: >>> >>>> Besides the others' advice that 2000+ keyspaces might be too much, the >>>> latest Java driver (2.0.11) includes an option to disable the Metadata API >>>> http://www.datastax.com/dev/blog/datastax-java-driver-2-0-11-released. >>>> I'm not sure at this moment if this has been merged into 2.1 already. >>>> >>>> On Sun, Sep 20, 2015 at 9:22 AM, joseph gao >>>> wrote: >>>> >>>>> cassandra: 2.1.7 >>>>> java driver: datastax java driver 2.1.6 >>>>> >>>>> Here is the problem: >>>>>My application uses 2000+ keyspaces, and will dynamically create >>>>> keyspaces and tables. And then in java client, the >>>>> Metadata.tokenMap.tokenToHost would use about 1g memory. so this will >>>>> cause >>>>> a lot of full gc. >>>>>As I see, the key of the tokenToHost is keyspace, and the value is >>>>> a tokenId_to_replicateNodes map. >>>>> >>>>>When I try to solve this problem, I find something not sure: all >>>>> keyspaces have same 'tokenId_to_replicateNodes' map. >>>>> My replication strategy of all keyspaces is : simpleStrategy and >>>>> replicationFactor is 3 >>>>> >>>>> So would it be possible if keyspaces use same strategy, the value >>>>> of tokenToHost map use a same map. So it would extremely reduce the memory >>>>> usage >>>>> >>>>> thanks a lot >>>>> >>>>> -- >>>>> -- >>>>> Joseph Gao >>>>> PhoneNum:15210513582 >>>>> QQ: 409343351 >>>>> >>>> >>>> >>>> >>>> -- >>>> Bests, >>>> >>>> Alex Popescu | @al3xandru >>>> Sen. Product Manager @ DataStax >>>> >>>> >>>> >>>> <http://cassandrasummit-datastax.com/?utm_campaign=summit15&utm_medium=summiticon&utm_source=emailsignature> >>>> >>> -- >>> Alexandre Dutra >>> Driver & Tools Engineer @ DataStax >>> >> >> >> >> -- >> -- >> Joseph Gao >> PhoneNum:15210513582 >> QQ: 409343351 >> > > > > -- > -- > Joseph Gao > PhoneNum:15210513582 > QQ: 409343351 > -- Bests, Alex Popescu | @al3xandru Sen. Product Manager @ DataStax
Re: Spark Cassandra Java Connector: records missing despite consistency=ALL
Dennis, You'll have better chances to get an answer on the spark-cassandra-connector mailing list https://groups.google.com/a/lists.datastax.com/forum/#!forum/spark-connector-user or on IRC #spark-cassandra-connector On Wed, Jan 13, 2016 at 4:17 AM, Dennis Birkholz wrote: > Hi together, > > we Cassandra to log event data and process it every 15 minutes with Spark. > We are using the Cassandra Java Connector for Spark. > > Randomly our Spark runs produce too few output records because no data is > returned from Cassandra for a several minutes window of input data. When > querying the data (with cqlsh), after multiple tries, the data eventually > becomes available. > > To solve the problem, we tried to use consistency=ALL when reading the > data in Spark. We use the > CassandraJavaUtil.javafunctions().cassandraTable() method and have set > "spark.cassandra.input.consistency.level"="ALL" on the config when creating > the Spark context. The problem persists but according to > http://stackoverflow.com/a/25043599 using a consistency level of ONE on > the write side (which we use) and ALL on the READ side should be sufficient > for data consistency. > > I would really appreciate if someone could give me a hint how to fix this > problem, thanks! > > Greets, > Dennis > > P.s.: > some information about our setup: > Cassandra 2.1.12 in a two Node configuration with replication factor=2 > Spark 1.5.1 > Cassandra Java Driver 2.2.0-rc3 > Spark Cassandra Java Connector 2.10-1.5.0-M2 > -- Bests, Alex Popescu | @al3xandru Sen. Product Manager @ DataStax
Re: Session timeout
On Fri, Jan 29, 2016 at 8:17 AM, oleg yusim wrote: > Thanks for encouraging me, I kind of grew a bit desperate. I'm security > person, not a Cassandra expert, and doing security assessment of Cassandra > DB, I have to rely on community heavily. I will put together a composed > version of all my previous queries, will title it "Security assessment > questions" and will post it once again. Oleg, I'll apologize in advance if my answer will sound initially harsh. I've been following your questions (mostly because I find them interesting), but I've never jumped to answer any of them as I confess not knowing the purpose of your research/report makes me caution (e.g. are you doing this for your current employer evaluating the future use of the product? are you doing this for an analyst company? are you planning to sell this report? etc. etc). -- Bests, Alex Popescu | @al3xandru Sen. Product Manager @ DataStax
Re: Cassandra driver class
I think both of those options expect a JDBC driver, while the DataStax Java driver is not one. As a side note, if you'd provide a more detailed description of the setup you want to get and post it to the Java driver mailing list https://groups.google.com/a/lists.datastax.com/forum/#!forum/java-driver-user, chances of getting an answer will be higher. On Fri, Jan 29, 2016 at 9:56 AM, KAMM, BILL wrote: > I’m just getting started with Cassandra, and am trying to integrate it > with JBoss. I’m configuring the standalone-ha-full.xml file, but don’t > know what to use for the driver class. For example, I have this: > > > > > > > > com.datastax.driver.core. > > > > > > > > What do I replace “” with? > > > > Is “com.datastax.driver.core” even correct, or am I going down the wrong > path? I am using the DataStax 2.0.2 driver, with Cassandra 2.0.8. > > > > Should I be using instead of ? > > > > Does anybody have a working example they can share? Any help to get me > going would be appreciated. Thanks. > > > > Bill > > > > > -- Bests, Alex Popescu | @al3xandru Sen. Product Manager @ DataStax
Re: Java Driver Question
On Tue, Feb 2, 2016 at 8:12 AM, Richard L. Burton III wrote: > is this behavior only related to the Java Drivers? All DataStax drivers for Cassandra provide the node discovery feature and are aware of the cluster topology. -- Bests, Alex Popescu | @al3xandru Sen. Product Manager @ DataStax
Re: Schema Versioning
On Wed, Feb 10, 2016 at 12:05 PM, Joe Bako wrote: > Modern RDBMS tools can compare schemas between DDL object definitions and > live databases and generate change scripts accordingly. Older techniques > included maintaining a version and script table in the database, storing > schema change scripts in a sequential fashion on disk, and iterating over > them to apply them against the target database based on whether they had > been run previously or not (indicated in the script table). Using DevCenter will give you some of these features (and future versions will add more). Just to give you a quick example, if using DevCenter to make schema changes it will offer the options of saving the final definition or just the set of changes applied (to an existing CQL file or a new one). -- Bests, Alex Popescu | @al3xandru Sen. Product Manager @ DataStax
