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From Brian O'Neill <b...@alumni.brown.edu>
Subject Re: Proposal: freeze Thrift starting with 2.1.0
Date Wed, 12 Mar 2014 14:12:28 GMT

just when you thought the thread diedŠ


First, let me say we are *WAY* off topic.  But that is a good thing.
I love this community because there are a ton of passionate, smart people.
(often with differing perspectives ;)

RE: Reporting against C* (@Peter Lin)
We¹ve had the same experience.  Pig + Hadoop is painful.  We are
experimenting with Spark/Shark, operating directly against the data.
http://brianoneill.blogspot.com/2014/03/spark-on-cassandra-w-calliope.html

The Shark layer gives you SQL and caching capabilities that make it easy to
use and fast (for smaller data sets).  In front of this, we are going to add
dimensional aggregations so we can operate at larger scales.  (then the Hive
reports will run against the aggregations)

RE: REST Server (@Russel Bradbury)
We had moderate success with Virgil, which was a REST server built directly
on Thrift.  We built it directly on top of Thrift, so one day it could be
easily embedded in the C* server itself.   It could be deployed separately,
or run an embedded C*.  More often than not, we ended up running it
separately to separate the layers.  (just like Titan and Rexster)  I¹ve
started on a rewrite of Virgil called Memnon that rides on top of CQL. (I¹d
love some help)
https://github.com/boneill42/memnon

RE: CQL vs. Thrift
We¹ve hitched our wagons to CQL.  CQL != Relational.
We¹ve had success translating our ³native² schemas into CQL, including all
the NoSQL goodness of wide-rows, etc.  You just need a good understanding of
how things translate into storage and underlying CFs.  If anything, I think
we could add some DESCRIBE information, which would help users with this,
along the lines of:
(https://issues.apache.org/jira/browse/CASSANDRA-6676)

CQL does open up the *opportunity* for users to articulate more complex
queries using more familiar syntax.  (including future things such as joins,
grouping, etc.)   To me, that is exciting, and again ‹ one of the reasons we
are leaning on it.

my two cents,
brian

---
Brian O'Neill
Chief Technology Officer


Health Market Science
The Science of Better Results
2700 Horizon Drive € King of Prussia, PA € 19406
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From:  Peter Lin <woolfel@gmail.com>
Reply-To:  <user@cassandra.apache.org>
Date:  Wednesday, March 12, 2014 at 8:44 AM
To:  "user@cassandra.apache.org" <user@cassandra.apache.org>
Subject:  Re: Proposal: freeze Thrift starting with 2.1.0


yes, I was looking at intravert last nite.

For the kinds of reports my customers ask us to do, joins and subqueries are
important. Having tried to do a simple join in PIG, the level of pain is
high. I'm a masochist, so I don't mind breaking a simple join into multiple
MR tasks, though I do find myself asking "why the hell does it need to be so
painful in PIG?" Many of my friends say "what is this crap!" or "this is
better than writing sql queries to run reports?"

Plus, using ETL techniques to extract summaries only works for cases where
the data is small enough. Once it gets beyond a certain size, it's not
practical, which means we're back to crappy reporting languages that make
life painful. Lots of big healthcare companies have thousands of MOLAP cubes
on dozens of mainframes. The old OLTP -> DW/OLAP creates it's own set of
management headaches.

being able to report directly on the raw data avoids many of the issues, but
that's my bias perspective.




On Wed, Mar 12, 2014 at 8:15 AM, DuyHai Doan <doanduyhai@gmail.com> wrote:
> "I would love to see Cassandra get to the point where users can define complex
> queries with subqueries, like, group by and joins" --> Did you have a look at
> Intravert ? I think it does union & intersection on server side for you. Not
> sure about join though..
> 
> 
> On Wed, Mar 12, 2014 at 12:44 PM, Peter Lin <woolfel@gmail.com> wrote:
>> 
>> Hi Ed,
>> 
>> I agree Solr is deeply integrated into DSE. I've looked at Solandra in the
>> past and studied the code.
>> 
>> My understanding is DSE uses Cassandra for storage and the user has both API
>> available. I do think it can be integrated further to make moderate to
>> complex queries easier and probably faster. That's why we built our own
>> JPA-like object query API. I would love to see Cassandra get to the point
>> where users can define complex queries with subqueries, like, group by and
>> joins. Clearly lots of people want these features and even google built their
>> own tools to do these types of queries.
>> 
>> I see lots of people trying to improve this with Presto, Impala, drill, etc.
>> To me, it's a natural progression as NoSql databases mature. For most people,
>> at some point you want to be able to report/analyze the data. Today some
>> people use MapReduce to summarize the data and ETL it into a relational
>> database or OLAP database for reporting. Even though I don't need CAS or
>> atomic batch for what I do in cassandra today, I'm sure in the future it will
>> be handy. From my experience in the financial and insurance sector, features
>> like CAS and "select for update" are important for the kinds of transactions
>> they handle. I'm bias, these kinds of features are useful and good addition
>> to cassandra.
>> 
>> These are interesting times in database land!
>> 
>> 
>> 
>> 
>> On Tue, Mar 11, 2014 at 10:57 PM, Edward Capriolo <edlinuxguru@gmail.com>
>> wrote:
>>> Peter, 
>>> Solr is deeply integrated into DSE. Seemingly this can not efficiently be
>>> done client side (CQL/Thrift whatever) but the Solandra approach was to
>>> embed Solr in Cassandra. I think that is actually the future client dev,
>>> allowing users to embedded custom server side logic into there own API.
>>> 
>>> Things like this take a while. Back in the day no one wanted cassandra to be
>>> heavy-weight and rejected ideas like read-before write operations. The
>>> common advice was "do them client side". Now in the case of collections
>>> sometimes they do read-before-write and it is the "stuff users want".
>>> 
>>> 
>>> 
>>> On Tue, Mar 11, 2014 at 10:07 PM, Peter Lin <woolfel@gmail.com> wrote:
>>>> 
>>>> I'll give you a concrete example.
>>>> 
>>>> One of the things we often need to do is do a keyword search on
>>>> unstructured text. What we did in our tooling is we combined solr with
>>>> cassandra, but we put an Object API infront of it. The API is inspired by
>>>> JPA, but designed specifically to fit our needs.
>>>> 
>>>> the user can do queries with like %blah% and behind the scenes we issues
a
>>>> query to solr to find the keys and then query cassandra for the records.
>>>> 
>>>> With plain Cassandra, the developer has to manually do all of this stuff
>>>> and integrate solr. Then they have to know which system to query and in
>>>> what order.  Our tooling lets the user define the schema in a modeler. Once
>>>> the model is done, it compiles the classes, configuration files, data
>>>> access objects and unit tests.
>>>> 
>>>> when the application makes a call, our query classes handle the details
>>>> behind the scene. I know lots of people would like to see Solr integrated
>>>> more deeply into Cassandra and CQL. I hope it happens in the future. If
>>>> DataStax accepts my talk, we will be showing our temporal database and
>>>> modeler in september.
>>>> 
>>>> 
>>>> 
>>>> 
>>>> On Tue, Mar 11, 2014 at 9:54 PM, Steven A Robenalt <srobenal@stanford.edu>
>>>> wrote:
>>>>> I should add that I'm not trying to ignite a flame war. Just trying to
>>>>> understand your intentions.
>>>>> 
>>>>> 
>>>>> On Tue, Mar 11, 2014 at 6:50 PM, Steven A Robenalt <srobenal@stanford.edu>
>>>>> wrote:
>>>>>> Okay, I'm officially lost on this thread. If you plan on forking
>>>>>> Cassandra to preserve and continue to enhance the Thrift interface,
you
>>>>>> would also want to add a bunch of relational features to CQL as part
of
>>>>>> that same fork?
>>>>>> 
>>>>>> 
>>>>>> On Tue, Mar 11, 2014 at 6:20 PM, Edward Capriolo <edlinuxguru@gmail.com>
>>>>>> wrote:
>>>>>>> "one of the things I'd like to see happen is for Cassandra to
support
>>>>>>> queries with disjunction, exist, subqueries, joins and like.
In theory
>>>>>>> CQL could support these features in the future. Cassandra would
need a
>>>>>>> new query compiler and query planner. I don't see how the current
design
>>>>>>> could do these things without a significant redesign/enhancement.
In a
>>>>>>> past life, I implemented an inference rule engine, so I've spent
over
>>>>>>> decade studying and implementing query optimizers. All of these
things
>>>>>>> can be done, it's just a matter of people finding the time to
do it."
>>>>>>> 
>>>>>>> I see what your saying. CQL started as a way to make slice easier
but it
>>>>>>> is not even a query language, retrofitting these things is going
to be
>>>>>>> very hard.
>>>>>>> 
>>>>>>> 
>>>>>>> 
>>>>>>> On Tue, Mar 11, 2014 at 7:45 PM, Peter Lin <woolfel@gmail.com>
wrote:
>>>>>>> 
>>>>>>> I have no problems maintain my own fork :) or joining others
forking
>>>>>>> cassandra.
>>>>>>> 
>>>>>>> I'd be happy to work with you or anyone else to add features
to thrift.
>>>>>>> That's the great thing about open source. Each person can scratch
a
>>>>>>> technical itch and do what they love. I see lots of potential
for
>>>>>>> Cassandra and many of them include improving thrift to make it
happen.
>>>>>>> Some of the features in theory "could" be done in CQL, but not
with the
>>>>>>> current design.
>>>>>>> 
>>>>>>> one of the things I'd like to see happen is for Cassandra to
support
>>>>>>> queries with disjunction, exist, subqueries, joins and like.
In theory
>>>>>>> CQL could support these features in the future. Cassandra would
need a
>>>>>>> new query compiler and query planner. I don't see how the current
design
>>>>>>> could do these things without a significant redesign/enhancement.
In a
>>>>>>> past life, I implemented an inference rule engine, so I've spent
over
>>>>>>> decade studying and implementing query optimizers. All of these
things
>>>>>>> can be done, it's just a matter of people finding the time to
do it.
>>>>>>> 
>>>>>>> 
>>>>>>> 
>>>>>>> 
>>>>>>> On Tue, Mar 11, 2014 at 6:17 PM, Edward Capriolo <edlinuxguru@gmail.com>
>>>>>>> wrote:
>>>>>>> Peter,
>>>>>>> 
>>>>>>> My advice. Do not bother. I have become very active recently
in
>>>>>>> attempting to add features to thrift. I had 4 open tickets I
was
>>>>>>> actively working on. (I even found two bugs in the Cassandra
in the
>>>>>>> process).
>>>>>>> 
>>>>>>> People were aware of this and still called this vote. Several
commit
>>>>>>> people have voted in a +1 and my -1 vote is non binding. It is
a clear
>>>>>>> message: The committers are unwilling to accept new thrift features
even
>>>>>>> if said features are contributed by others.
>>>>>>> 
>>>>>>> Edward
>>>>>>> 
>>>>>>> 
>>>>>>> 
>>>>>>> On Tue, Mar 11, 2014 at 5:51 PM, Peter Lin <woolfel@gmail.com>
wrote:
>>>>>>> 
>>>>>>> My bias opinion, just because some member of cassandra develop
want to
>>>>>>> abandon Thrift, I see benefits of continuing to improve it.
>>>>>>> 
>>>>>>> The great thing about open source is that as long as some people
want to
>>>>>>> keep working on it and improve it, it can happen. I plan to do
my best
>>>>>>> to keep Thrift going, since it gives me fine grain control that
I want
>>>>>>> and need. If the ultimate goal of Cassandra is to be "as close
to SQL"
>>>>>>> as practical, my bias take is use a NewSQL database that gives
you the
>>>>>>> full power of subqueries, like, exists and disjunction.
>>>>>>> 
>>>>>>> When customers ask me which database to choose and they really
want
>>>>>>> Relational model, I tell them use NewSql. I love that Cassandra
sits
>>>>>>> between NoSql and NewSql. There are things I do in Cassandra
today that
>>>>>>> are much harder in NewSql or NoSql document databases. NewSql
database
>>>>>>> can scale to similar sizes, so the "big" part of big data won't
be a
>>>>>>> significant advantage forever. Looking at some of the recent
NewSql
>>>>>>> performance numbers, it's clear the gap is closing.
>>>>>>> 
>>>>>>> peter
>>>>>>> 
>>>>>>> 
>>>>>>> 
>>>>>>> On Tue, Mar 11, 2014 at 3:59 PM, Tyler Hobbs <tyler@datastax.com>
wrote:
>>>>>>> 
>>>>>>> On Tue, Mar 11, 2014 at 2:41 PM, Shao-Chuan Wang
>>>>>>> <shaochuan.wang@bloomreach.com> wrote:
>>>>>>> 
>>>>>>> So, does anyone know how to do "describing the splits" and "describing
>>>>>>> the local rings" using native protocol?
>>>>>>> 
>>>>>>> For a ring description, you would do something like "select peer,
tokens
>>>>>>> from system.peers".  I'm not sure about describe_splits().
>>>>>>>  
>>>>>>> 
>>>>>>> Also, cqlsh uses python client, which is talking via thrift protocol
>>>>>>> too. Does it mean that it will be migrated to native protocol
soon as
>>>>>>> well?
>>>>>>> 
>>>>>>> Yes: https://issues.apache.org/jira/browse/CASSANDRA-6307
>>>>>>> 
>>>>>>> 
>>>>>>> -- 
>>>>>>> Tyler Hobbs
>>>>>>> DataStax <http://datastax.com/>
>>>>>>> 
>>>>>>> 
>>>>>>> 
>>>>>>> 
>>>>>> 
>>>>>> 
>>>>>> 
>>>>>> -- 
>>>>>> Steve Robenalt
>>>>>> Software Architect
>>>>>> HighWire | Stanford University
>>>>>> 425 Broadway St, Redwood City, CA 94063
>>>>>> 
>>>>>> srobenal@stanford.edu
>>>>>> http://highwire.stanford.edu
>>>>>> 
>>>>>> 
>>>>>> 
>>>>>> 
>>>>>> 
>>>>> 
>>>>> 
>>>>> 
>>>>> -- 
>>>>> Steve Robenalt
>>>>> Software Architect
>>>>> HighWire | Stanford University
>>>>> 425 Broadway St, Redwood City, CA 94063
>>>>> 
>>>>> srobenal@stanford.edu
>>>>> http://highwire.stanford.edu
>>>>> 
>>>>> 
>>>>> 
>>>>> 
>>>>> 
>>>> 
>>> 
>> 
> 




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