That is great. We can probably pick the most recent Java driver and
Cassandra version then. Since it addresses couple of old issues.

Regarding Spark SQL for querying Cassandra I would let other contributors
suggest.

On Thu, Jul 23, 2015 at 11:04 PM, Ajay <[email protected]> wrote:

> Thanks Yash.
>
> In Between, ALLOW FILTERING is supported in Cassandra Java driver [1]. What
> is the Cassandra and Java driver version we plan to support?. I have worked
> on Cassandra 2.0.x and 2.1.x and Java driver 2.1.x and ALLOW FILTERING
> worked.
>
> Secondly, as you mentioned I am aware of these limitation in CQL. But more
> features recently added in Cassandra 2.2.x. Also, other option to work
> around this to use Cassandra Spark connector and use Spark SQL.
>
> 1)
>
> http://docs.datastax.com/en/drivers/java/2.0/com/datastax/driver/core/querybuilder/Select.html
>
>
> On Thu, Jul 23, 2015 at 10:07 PM, Yash Sharma <[email protected]> wrote:
>
> > Just to add on...
> >
> > There will be few challenges to support entire SQL on Cassandra however.
> > Last time I tried translating SQL to CQL I faced couple of scenarios -
> >
> > 1. Filtering non indexed column in Cassandra
> > 2. Filtering by subset of primary key
> > 3. OR condition in where clause
> >
> > You can probably start without these being a blocker - In parallel we can
> > discuss how this can be implemented on our stack. Others can provide
> their
> > opinions here.
> >
> > Hope its helpful.
> >
> > -----
> > Examples:
> > Here 'trending_now' is a dummy table with (id, rank, pog_id) where
> > (id,rank) is primary key pair.
> >
> > 1.
> > cqlsh:recsys> select * from trending_now where pog_id=10004 ;
> > Bad Request: No indexed columns present in by-columns clause with Equal
> > operator
> >
> > 2.
> > cqlsh:recsys> select * from trending_now where rank=4;
> > Bad Request: Cannot execute this query as it might involve data filtering
> > and thus may have unpredictable performance. If you want to execute this
> > query despite the performance unpredictability, use ALLOW FILTERING
> > P.S. ALLOW FILTERING is not permitted in Cassandra java driver as of now.
> >
> > 3.
> > cqlsh:recsys> select * from trending_now where rank=4 or id='id0004';
> > Bad Request: line 1:40 missing EOF at 'or'
> >
> > 4. Valid Query:
> > cqlsh:recsys> select * from trending_now where id='id0004' and rank=4;
> >
> >  id     | rank | pog_id
> > --------+------+--------
> >  id0004 |    4 |  10002
> >
> >
> > On Thu, Jul 23, 2015 at 9:45 PM, Yash Sharma <[email protected]> wrote:
> >
> > > The basic idea is to translate the Lens Query plan (Which is a Hive
> AST)
> > > to the DataStore specific Plan/Query.
> > >
> > > The best example I can think of right now is the Elastic Search patch
> by
> > > Amruth. You can go through the JIRA [1] for the detailed discussion and
> > the
> > > Review Board [2] for code reference.
> > >
> > > Best regards
> > >
> > > 1. https://issues.apache.org/jira/browse/LENS-252
> > > 2. https://reviews.apache.org/r/36434
> > >
> > > On Thu, Jul 23, 2015 at 9:30 PM, Ajay <[email protected]> wrote:
> > >
> > >> Thanks Yash.
> > >>
> > >> Is there any documentation or WIKI on the Lens Driver. I am going
> > through
> > >> the code as well.
> > >>
> > >> Thanks
> > >> Ajay
> > >>
> > >>
> > >> On Thu, Jul 23, 2015 at 12:01 PM, Yash Sharma <[email protected]>
> > wrote:
> > >>
> > >> > Hi Ajay,
> > >> > Welcome to the Lens Dev.
> > >> > We do have plans for a Cassandra driver [1] for Lens but no one has
> > >> picked
> > >> > it up yet. It would be great if you can pick up the task and submit
> a
> > >> patch
> > >> > for review.
> > >> >
> > >> > Also drop a note on the list in case you stumble upon any issue.
> > Someone
> > >> > will always be around to help you out.
> > >> >
> > >> >
> > >> > 1. https://issues.apache.org/jira/browse/LENS-654
> > >> >
> > >> > On Thu, Jul 23, 2015 at 11:41 AM, Ajay <[email protected]>
> wrote:
> > >> >
> > >> > > Hi,
> > >> > >
> > >> > > I recently noticed about Apache Lens project. Currently we are
> > >> building
> > >> > > REST APIs for Apache Cassandra (proprietary) as there no such
> Apache
> > >> open
> > >> > > source project exists. Now as Lens supports REST APIs for Hadoop
> and
> > >> > JDBC,
> > >> > > I want to know is there any plan to support for Apache Cassandra
> as
> > >> its
> > >> > > support CQL and Spark SQL (thru Spark connector) which are more
> SQL
> > >> like.
> > >> > > If yes, I wish to know the details and contribute as well.
> > >> > >
> > >> > > Thanks
> > >> > > Ajay
> > >> > >
> > >> >
> > >>
> > >
> > >
> >
>

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