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From Mohit Anchlia <>
Subject Re: Programmatically allow only one out of two types of rows in a CF to enter the CACHE
Date Sat, 29 Oct 2011 19:21:39 GMT
On Sat, Oct 29, 2011 at 11:23 AM, Aditya Narayan <> wrote:
> @Mohit:
> I have stated the example scenarios in my first post under this heading.
> Also I have stated above why I want to split that data in two rows & like
> Ikeda below stated, I'm too trying out to prevent the frequently accessed
> rows being bloated with large data & want to prevent that data from entering
> cache as well.

I think you are missing the point. You don't get any benefit
(performance, access), you are already breaking it into 2 rows.

Also, I don't know of any way where you can selectively keep the rows
or keys in the cache. Other than having some background job that keeps
the cache hot with those keys/rows you only have one option of keeping
it in different CF since you are already breaking a row in 2 rows.

>> Okay so as most know this practice is called a wide row - we use them
>> quite a lot. However, as your schema shows it will cache (while being
>> active) all the row in memory.  One way we got around this issue was to
>> basically create some materialized views of any more common data so we can
>> easily get to the minimum amount of information required without blowing too
>> much memory with the larger representations.
> Yes exactly this is problem I am facing but I want to keep the both the
> types(common + large/detailed) of data in single CF so that it could server
> 'two materialized views'.
>> My perspective is that indexing some of the higher levels of data would be
>> the way to go - Solr or elastic search for distributed or if you know you
>> only need it local just use a caching solution like ehcache
> What do you mean exactly by  "indexing some of the higher levels of data" ?
> Thanks you guys!
>> Anthony
>> On 28/10/2011, at 21:42 PM, Aditya Narayan wrote:
>> > I need to keep the data of some entities in a single CF but split in two
>> > rows for each entity. One row contains an overview information for the
>> > entity & another row contains detailed information about entity. I am
>> > wanting to keep both rows in single CF so they may be retrieved in a single
>> > query when required together.
>> >
>> > Now the problem I am facing is that I want to cache only first type of
>> > rows(ie, the overview containing rows) & avoid second type rows(that
>> > contains large data) from getting into cache.
>> >
>> > Is there a way I can manipulate such filtering of cache entering rows
>> > from a single CF?
>> >
>> >

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