Re: Which way to Cassandraville?

2014-07-20 Thread DuyHai Doan
> Having said that, what Java clients should I be looking at? Are there > any reasonably mature PoJo mapping techs for Cassandra analogous to > Hibernate? The Java Driver offers a basic object mapper in the mapper module. If you look for something more evolved, have a look at http://doanduyhai.gi

Re: How to prevent writing to a Keyspace?

2014-07-20 Thread Vivek Mishra
Create different user and assign role and privileges. Create a user like guest and grant select only to that user. That way user cannot modify data in specific keyspace or column family. http://www.datastax.com/documentation/cql/3.0/cql/cql_reference/grant_r.html -Vivek On Mon, Jul 21, 2014 at

RE: How to prevent writing to a Keyspace?

2014-07-20 Thread Lu, Boying
Thanks a lot ☺ But I think authorization and authentication do little help here. Once we allow an user to read the keyspace, how can we prevent him from writing DB without Cassandra’s help? Is there any way to support ‘read-only’ some keyspace in Cassandra ? e.g. set some specific strategy? B

Re: Which way to Cassandraville?

2014-07-20 Thread Kevin Burton
> > > I just finished reading "Cassandra: The Definitive Guide" which seems > pretty out of date and while very informative as to the technology that > Cassandra uses, was not very helpful from the perspective of an > application developer. > > Very very out of date… > Having said that, what Java

Re: horizontal query scaling issues follow on

2014-07-20 Thread Diane Griffith
I am running tests again across different number of client threads and number of nodes but this time I tweaked some of the timeouts configured for the nodes in the cluster. I was able to get better performance on the nodes at 10 client threads by upping 4 timeout values in cassandra.yaml to 24

Which way to Cassandraville?

2014-07-20 Thread jcllings
So I'm a Java application developer and I'm trying to find entry points for learning to work with Cassandra. I just finished reading "Cassandra: The Definitive Guide" which seems pretty out of date and while very informative as to the technology that Cassandra uses, was not very helpful from the pe

Re: estimated row count for a pk range

2014-07-20 Thread DuyHai Doan
1) Use separate counter to count number of entries in each column family but it will require you to manage the counting manually 2) SELECT DISTINCT partitionKey FROM Normally this query is optimized and is much faster than a SELECT *. However if you have a very big number of distinct partitio

estimated row count for a pk range

2014-07-20 Thread tommaso barbugli
Hello, Lately I collapsed several (around 1k) column families in a bunch (100) of column families. To keep data separated I have added an extra column (family) which is part of the PK. While previous approach allowed me to always have a clear picture of every column family's size; now I have no ot

Caffinitas Mapper - Java object mapper for Apache Cassandra

2014-07-20 Thread Robert Stupp
Hi all, I've just released the first beta version of Caffinitas Mapper. Caffinitas Mapper is an advanced Java object mapper for Apache Cassandra NoSQL database. It offers an annotation based declaration model with a wide range of built-in features like JPA style inheritance with table-per-class