I have generated a Thrift lib for Cassandra targeting JavaScript from the latest Thrift build in SVN. However, I noticed in the provided js thrift client library the following statement: This client can only speak the JSON Protocol and the only supported transport is AJAX. Does anyone know if the JSON protocol is compatible wi...
Cassandra offers controlled consistency like "write to 2 nodes and tell me it's done". Two "master" nodes and some slaves makes system good failover. MongoDB offers replication pairs - simmilar failover force like cassandra? Is there any other database with this form-box functionality? ...
I am going through apache cassandra and working on sample data insertion, retrieving etc. The documentation is very limited. I am interested in knowing can we completely replace relation db like mysql/ oracle with cassandra? does cassandra support rollback/ commit? does cassandra clients (thrift/ hector) support fetching associated o...
Hi all, I have found no way to translate a simple select like SELECT * FROM USER into Cassandra. Is it possible to simply retrieve all the keys in a ColumnFamily? The only one I have found is a select with a key range (get_range_slices). Is there a way to get the entire key list without the need to define a key range? Thanks Tobia Losc...
Hi, If I delete every keys in a ColumnFamily in a Cassandra db using remove(key), then if I use get_range_slices, rows are still there but without columns. How could I remove entire rows? Thanks Tobia Loschiavo ...
Hi there, I'm building a system that tracks and verifies ad impressions and clicks. This means that there are a lot of insert commands (about 90/second average, peaking at 250) and some read operations, but the focus is on performance and making it blazing-fast. The system is currently on MongoDB, but I've been introduced to Cassandra ...
Does cassandra replicates only on write procedure (with choosen consistency level)? Is there any auto-replicate option for absent nodes, if i want symetric data in every node? If I plug in new node to cluster there is no auto replication - how to sync data from others nodes with new one? If I want replication like multimaster (2 nodes)...
i am wondering because i searched the pdf "xxx the definitive guide" and "beginning xxx" for the word "inheritance" but i didn't find anything? am i missing something? because i am doing a tablePerHierarchy inheritance with hibernate and mysql, does that become deprecated for some reason in xxx? (replace xxx with the "not only sql" data...
What does going with a document based NoSQL option buy you over a KV store, and vice-versa? ...
What does going with a document based NoSQL option buy you over a KV store, and vice-versa? ...
I'm fairly new to Apache Cassandra and nosql in general. In SQL I can do aggregate operations like: SELECT country, sum(age) / count(*) AS averageAge FROM people GROUP BY country; This is nice because it is calculated within the DB, rather than having to move every row in the 'people' table into the client layer to do the calcul...
We're still evaluating Cassandra for our data store. As a very simple test, I inserted a value for 4 columns into the Keyspace1/Standard1 column family on my local machine amounting to about 100 bytes of data. Then I read it back as fast as I could by row key. I can read it back at 160,000/second. Great. Then I put in a million similar...
I'm currently architecting a system that must be capable of dealing with tens of thousands of writes per second. I am more-or-less settled on using Apache Cassandra for the persistence layer, and will be using Java for the application layer, but there are situations where I need to quickly access data in a way that picks up any changes ...
I'm performing a superSlice operation on a column family that looks like this: SuperColumn Family: UserActivity{ User1{ Activity1{ //activity detail columns } Activity2{ //activity detail columns } . . . . } } Test case: 1. Inserted 5 users ...
Hi All, I have a question regarding inserting data to Cassandra. I have deleted a row key from a Column Family(CF) after some time I am trying insert data with the same rowkey. The program gets executed but when I try to access the data with the rowkey from command line I get zero results. Why is this happening? I know there is some ...
I've a problem storing 50Gb of logs each day in a distributed environment. I looked at Hadoop HDFS but because it has problems running on Windows infrastructure, lack of multi language filesystem API it doesn't suit me very well. Cassandra on the other hand is very easy to deploy on any platform. The only big problem I'm facing is a disk...
i need to do something like this on apache cassandra, SELECT * FROM mytable where address = "%indonesia%" any idea how to do it on cassandra? ...
Two days ago i started learning Cassandra in my internship, they gave me a learning about Cassandra and i found some codes from the net.There is no errors on the code syntatically but when i run the code i get errors like : InvalidRequestException(why:Keyspace Blog does not exist in this schema.) at org.apache.cassandra.thrift...
Hi all, We would like to protect the Cassandra against man-in-the-middle attacks. Is there any way to configure Cassandra in a way that the client-server and server-server (replication) communications are SSL encrypted? thank you ...
I am trying to implement a transaction system for Cassandra with the help of ZooKeeper. Since I don't think I have enough experience in database implementation, I would like to know if my idea would work in principle, or is there any major flaw. Here is the high level description of the steps: identify all the rows(keys) and columns t...