Hello Mark,

The article is not technical, covers only the top of the iceberg and this is 
probably why it confused you a lot.

In short, the conclusion you got

> I'm especially interested in not having to migrate any schema's,  nor having 
> to pre-load the data into the cache.  (lazy load), which the articles imply. 

is not 100% correct.

Cassandra is a 3rd party store for Ignite (as any RDBMS or NoSQL database) and 
you should create corresponding Ignite schema and fully pre-load data in RAM if 
you plan using SQL. That’s not required only if Ignite Native Persistence is 
used as a disk store. See the differences here:
https://apacheignite.readme.io/v2.1/docs/distributed-persistent-store#section-ignite-native-vs-3rd-party-persistence

Basically, if to follow the earlier provided Cassandra integration doc you will 
be able to stick Ignite and Cassandra together.
 
P.S.
I’ve updated the broken links. Thanks for reporting!

—
Denis

> On Aug 31, 2017, at 12:29 PM, Mark Farnan <[email protected]> wrote:
> 
> Hi Ilya, 
> 
> That documentation I saw,  however it seems to describe only using Cassandra 
> as a Persistant store for  Ignite Caches,   i.e.   
> 
> "Ignite Cassandra module implements persistent store 
> <https://apacheignite.readme.io/docs/persistent-store> for Ignite caches by 
> utilizing Cassandra <http://cassandra.apache.org/>as a persistent storage for 
> expired cache records. 
> It functions pretty much the same way like CacheJdbcBlobStore 
> <https://apacheignite.readme.io/docs/persistent-store#cachejdbcblobstore> and 
> CacheJdbcPojoStore 
> <https://apacheignite.readme.io/docs/persistent-store#cachejdbcpojostore>and 
> provides such benefits:"
> 
> It dosn't seem to describe anywhere, how to set it up over an existing large 
> cassandra table structure to act as a cache and SQL query mechanism for it.   
> Nor how to deal with the fact you can't have it all in memory and how Writes 
> and Reads would be handled etc. 
> Also several of the links on the page are broken. 
> 
> Ideally want to be able to run ad-hoc SQL queries over the data, including 
> joins etc. \ 
> 
> I agree there are config examples, AWS etc,   but  they all seem to me, to be 
> for persistance of general cache,  BLOB or POJO,   not for what the InfoWorld 
> article described. 
> 
> Unless I'm missing something obvious !. 
> 
> 
> Regards 
> 
> Mark. 
> 
> 
> 
> 
> 
> From:        Ilya Kasnacheev <[email protected]> 
> To:        [email protected], 
> Date:        08/31/2017 06:56 PM 
> Subject:        Re: Ignite as Cache and Query layer for Cassandra. 
> 
> 
> 
> Hello Mark,
> 
> I have found some documentation on how to do what the article describes:
> 
> "Apache Ignite can be inserted between Apache Cassandra and an existing 
> application layer with no changes to the Cassandra data and only minimal 
> changes to the application"
> 
> https://apacheignite-mix.readme.io/docs/ignite-with-apache-cassandra 
> <https://apacheignite-mix.readme.io/docs/ignite-with-apache-cassandra>
> 
> On the left you can see there are config examples, tests, AWS configuration, 
> etc.
> 
> Hope it's good enough. 
> 
> 
> -- 
> Ilya Kasnacheev 
> 
> 2017-08-31 16:15 GMT+03:00 Mark Farnan <[email protected] 
> <mailto:[email protected]>>: 
> Howdy, 
> 
> I'm currently evaluating Ignite for a project, and am looking for some 
> guidance and project sample for using Ignite over Cassandra as a cache and 
> query layer.   
> Note: The Cassandra database and schema already exists and is mature.   
> 
> In a Recent Infoworld post,   
> (https://www.infoworld.com/article/3191895/application-development/light-a-fire-under-cassandra-with-apache-ignite.html
>  
> <https://www.infoworld.com/article/3191895/application-development/light-a-fire-under-cassandra-with-apache-ignite.html>)
>  it stated 
> 
> "No remodeling of Cassandra data 
> Apache Ignite reads from Apache Cassandra and other NoSQL databases, so 
> moving Cassandra data into Ignite requires no data modification. The data 
> schema can also be migrated directly into Ignite as is. " 
> 
> However, I can't find in any documentation,  or online articles,  guidance on 
> just how to do this and there are no links in the article. 
>   - The Ignite docs /cassandra section appear to only cover using Cassandra 
> as a persistence layer,  not for going over and caching / querying an 
> existing schema.   (unless I'm missing something obvious !) 
>   - The Youtube video cuts out to blank at the end, so no links are shown.    
> The  links on the slideshare document appear to be broken. 
>   -  Can't find any git hub for examples on how to do this (especially not 
> for the couple you tube vids) 
> 
> Can anyone please point me to some working sample code and/or documentation 
> on how to do this ? 
> 
> I'm especially interested in not having to migrate any schema's,  nor having 
> to pre-load the data into the cache.  (lazy load), which the articles imply. 
> Also some of the data would be too large to load it all into Ram anyway. 
> 
> 
> Any assistance greatly appreciated.   
> 
> 
> Regards 
> 
> Mark. 
> 

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