[infinispan-dev] Continuous Query Caching

[Navin Surtani]

On 29 Sep 2009, at 09:57, Mircea Markus wrote:

> Hi,
>
> Again, this is a feature from Coherence[1].
>
> Basic idea is to execute a query against the cache, and hold the  
> result object. This result object will always have up to date query  
> result; this means that whenever something is modified in the cache  
> the result itself is updated.

So I'm guessing a use case could be something like putting objects  
into one node in a cluster and then running a query on a separate node?


> Advantage: if one performs the same query very often(e.g. several  
> times every millisecond) the response will be fast and the system  
> will not be overloaded.
> E.g.
> Filter filter = new AndFilter(new EqualsFilter("getTrader", traderid),
>                               new EqualsFilter("getStatus",  
> Status.OPEN));
> ContinuousQueryCache cacheOpenTrades = new  
> ContinuousQueryCache(cache, filter);
>
> Iterator iter = cacheOpenTrades.entrySet().iterator(); //*this  
> entrySet call will be instant!*
>
> FOr a full list of scenario in which this can be used take a look at  
> [1].
> Shall we consider adding something similar?
I guess it would depend if we were thinking of keeping those  
iterators. There was the debate about pagination vs iterators so I  
guess it would depend on what happens with the debate.


>
> Cheers,
> Mircea
>
>
> [1] http://download.oracle.com/docs/cd/E14526_01/coh.350/e14509/continuousquery.htm#BABBEIAH
> _______________________________________________
> infinispan-dev mailing list
> infinispan-dev at lists.jboss.org
> https://lists.jboss.org/mailman/listinfo/infinispan-dev

Navin Surtani

Intern Infinispan
Intern JBoss Cache Searchable

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.jboss.org/pipermail/infinispan-dev/attachments/20090929/c3f0d0e5/attachment-0002.html