Cassandra does not comply with ACID like RDBMS but CAP. So Cassandra picks AP out of CAP and leaves it to the user for tuning consistency. I definitely cannot use Cassandra for core banking transac...

I intend to use apache flink for read/write data into cassandra using flink. I was hoping to use flink-connector-cassandra, I don't find good documentation/examples for the connector. Can you plea...

Using Cassandra, how do i see how many partitions were created base on how i created the primary key? I have been following a tutorial and it mentions to go to bin/cassandra-cli and use the LIST co...

I have a few questions regarding the integration of the two tools. Not technical questions and how to setup( i will have my fun with that later ) but more on the course of the project and the direc...

I have a production cassandra cluster of 6 nodes. I have made some changes to the cassandra.yaml file on one node and hence need to restart it. How can I do it without losing any data or causing an...

This is Cassandra 2.1.13 day2 for me. I've been through 10 min. cassandra tutorial at http://www.planetcassandra.org/try-cassandra/ on my local machine. % cqlsh -u cassandra -p cassandra % // crea...

In cassandra I have a list column type. I am new to spark and scala, and have no idea where to start. In spark I want get count of each values, is it possible to do so. Below is the dataframe +---...

I have a 4 node cluster with 16 core CPU and 100 GB RAM on each box (2 nodes on each rack). As of now, all are running with default JVM settings of Cassandra (v2.1.4). With this setting, each nod...

I am a java developer and am very new to Linux and Cassandra. I am using CentOS6. I am trying to install Cassandra3.4 in the Linux machine. I have followed the steps mentioned in here. Looks like ...

I tried setting up a 2 node Cassandra setup and it's quite done. Nodes are seems connected as shown below : Datacenter: datacenter1 ======================= Status=Up/Down |/ State=Normal/Leaving/J...

After posting a question and reading this and that articles, I still do not understand the relations between those three operations- Cassandra compaction tasks nodetool repair nodetool cleanup ...

I am using the datastax java driver for Apache Cassandra (v. 2.1.9) and I am wondering what should happen when I set replication_factor greater than number of nodes. I've read somewhere that Cassa...

I'm running my own version of cassandra on 127.0.1.1. I changed the rpc_address and also the address to 127.0.1.1. When I'm starting Opscenter I'm prompted to install agents and I'm doing so by the...

Theoretically, Cassandra allows up to 2 billion columns in a wide row. I have heard that in reality up to 50.000 cols/50 MB are fine; 50.000-100.000 cols/100 MB are OK but require some tuning; and...

I'm running a two node Datastax AMI cluster on AWS. Yesterday, Cassandra started refusing connections from everything. The system logs showed nothing. After a lot of tinkering, I discovered that th...

We have Cassandra 1.1.1 servers with Leveled Compaction Strategy. The system works so that there are read and delete operations. Every half a year we delete approximately half of the data while ne...

I am trying to understand how the Leveled Compaction Strategy in Cassandra works that guarantees 90% of all reads will be satisfied from a single sstable. From DataStax Doc: new sstables are a...

I am planning to use a Java object as a custom type and store it Cassandra. I am taking out 2 data members from the class and making them into primary key and keeping the rest of the data members i...

How would I write the CQL to get the most recent set of data from each row? I'm investigating transitioning from MSSQL to Cassandra and am starting to grasp the concepts. Lots of research has help...