Hello Collin, You mean to say you have made un-published modifications to Cassandra such that you can execute logic in Db in read and write path?
Do you have any plans to open your code base and document it? Praveen On Sun, Apr 22, 2012 at 10:43 PM, Colin Clark <colpcl...@gmail.com> wrote: > In my opinion, triggers/stored procedures are an absolute requirement for > any distributed database. > > We've been using stored procedures in Cassandra now for a while, we've > made modifications such that we don't really write directly anymore but > pass everything through either a default stored procedures (which is just > what was there before) or a dynamically loaded piece of java. > > These stored procedures can call other dynamically loaded pieces of java > as well - we don't have any plans to implement any scripting capabilities. > We can also 'select' from procedures. > > The idea of downloading data from a distributed data base for processing > flies in the face of what nosql and bigdata is all about - you've got to do > it in the db. > > On Apr 22, 2012, at 11:35 AM, Brian O'Neill wrote: > > > Praveen, > > > > We are certainly interested. To get things moving we implemented an > add-on for Cassandra to demonstrate the viability (using AOP): > > https://github.com/hmsonline/cassandra-triggers > > > > Right now the implementation executes triggers asynchronously, allowing > you to implement a java interface and plugin your own java class that will > get called for every insert. > > > > Per the discussion on 1311, we intend to extend our proof of concept to > be able to invoke scripts as well. (minimally we'll enable javascript, but > we'll probably allow for ruby and groovy as well) > > > > -brian > > > > On Apr 22, 2012, at 12:23 PM, Praveen Baratam wrote: > > > >> I found that Triggers are coming in Cassandra 1.2 ( > https://issues.apache.org/jira/browse/CASSANDRA-1311) but no mention of > any StoreProc like pattern. > >> > >> I know this has been discussed so many times but never met with any > initiative. Even Groovy was staged out of the trunk. > >> > >> Cassandra is great for logging and as such will be infinitely more > useful if some logic can be pushed into the Cassandra cluster nearer to the > location of Data to generate a materialized view useful for applications. > >> > >> Server Side Scripts/Routines in Distributed Databases could soon prove > to be the differentiating factor. > >> > >> Let me reiterate things with a use case. > >> > >> In our application we store time series data in wide rows with TTL set > on each point to prevent data from growing beyond acceptable limits. Still > the data size can be a limiting factor to move all of it from the cluster > node to the querying node and then to the application via thrift for > processing and presentation. > >> > >> Ideally we should process the data on the residing node and pass only > the materialized view of the data upstream. This should be trivial if > Cassandra implements some sort of server side scripting and CQL semantics > to call it. > >> > >> Is anybody else interested in a similar feature? Is it being worked on? > Are there any alternative strategies to this problem? > >> > >> Praveen > >> > >> > > > > -- > > Brian ONeill > > Lead Architect, Health Market Science (http://healthmarketscience.com) > > mobile:215.588.6024 > > blog: http://weblogs.java.net/blog/boneill42/ > > blog: http://brianoneill.blogspot.com/ > > > >
