Cassandra - transaction support

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...

Scraping data straight to Cassandra database

Can anyone help me with Cassandra database? Actually, I want to through the scraped data directly to Cassandra. Currently, I am using scrapy for parsing data from different websites. Thanks-in...

Whats the difference between Paxos and W+R>=N in Cassandra?

Dynamo-like databases (e.g. Cassandra) can enforce consistency by means of quorum, i.e. a number of synchronously written replicas (W) and a number of replicas to read (R) should be chosen in such...

How to check if a Cassandra table exists

Is there an easy way to check if table (column family) is defined in Cassandra using CQL (or API perhaps, using com.datastax.driver)? Right now I am leaning towards executing SELECT 1 FROM table...

Apache Cassandra: Unable to gossip with any seeds

I have built Cassandra server 2.0.3, then run it. It is starting and then stopped with messages: X:\MyProjects\cassandra\apache-cassandra-2.0.3-src\bin>cassandra.bat...

Cassandra/CQL: How to ALTER column1 type?

I have a number of existing Cassandra 2.0.0 CFs created by trift API and want to use Datastax DevCenter 1.1.1 and CQL3 in future, so I tried to change column types from blob-s to something more...

Cassandra cqlsh Unable to connect to any servers - 127.0.0.1:9160 (closed)> is already closed

I installed Cassandra on OSX. When trying to run cqlsh from /bin/, I get the following error: > Connection error: ('Unable to connect to any servers', {'127.0.0.1': >...

@ConfigurationProperties prefix not working

.yml file cassandra: keyspaceApp:junit solr: keyspaceApp:xyz Bean @Component @ConfigurationProperties(prefix="cassandra") public class CassandraClientNew { ...

Live Indexing DSE

I want to enable live indexing on my cluster. As per the steps here, I must increase the heap size to at least 20 GB. I have 3 nodes in my cluster, each having 32 GB of RAM. The current heap size...

Where is cassandra installed on mac? How to check the version?

I've installed cassandra on my mac. How do i check the path where it is installed? Also, How can i check the cassandra version installed on my mac?

Codec not found for requested operation: [timestamp <-> java.lang.Long]

I wrote this simple program in scala to query cassandra val session = cass.session lazy val stmt = cass.session.prepare( """ |select token(id), id, date, rId, tt | from foo |...

Can MySQL handle millions of users for my social networking app? MySQL Vs Other Database technologies?

We are developing a social networking app. Following are the features : Video/Photo sharing Ranking / Complex Algorithms Suggesions Other features similiar to Instagram/Facebook Platforms...

Cassandra 2.1 OutOfMemory

I have a Cassandra node with 64G ram (16GB heap, G1GC), and occasionally this happens: ERROR [Thrift:74] 2017-06-11 13:20:25,710 CassandraDaemon.java:229 - Exception in thread...

ERROR:No contact points for [cas_native] when running the lagom project in conductr sandbox locally and cassandra separately in local?

I have a lagom project and I am using external cassandra so the actual problem is when i am running my project on conductr locally using sandbox it is not able to detect cassandra running...

Cannot copy csv file inside a cassandra table

I create a standard csv file using COPY/TO and now I want to upload the content using COPY/FROM inside of another cassandra table. However, I get the following error: Failed to import 5000 rows:...

Thingsboard cluster setup

Building a Thingsboard cluster I need help setting up a Thingsboard cluster, the documentation online is very limited. The cluster will contain 2 Zookeeper nodes and 4 Thingsboard nodes with...

Spring Boot health check schedule

Is there any way to make Spring Actuator perform health check periodically? I'm thinking, maybe, there's an option to have some Runnable in my custom implementation of HealthIndicator, but for me...

Cassandra bulk load dsbulk - set<text> load issue

Trying to load a csv file into dse cassandra using the dsbulk utility. I am running into issues if the column is defined as set. copy command is successfully loading "{'bible', 'moses', 'ramses'}"...

Error from server: code=1300 [Replica(s) failed to execute read] message="Operation failed

Getting the below error while fetching 50k records from Cassandra using Python. Any suggestions please? Error from server: code=1300 [Replica(s) failed to execute read] message="Operation failed -...

Add Datacenter existing cluster

I try to add a dc to my existing cluster. I changed my networkTopologie with one keyspaces but new DC works like full replica. I only change one keyspace topologie but other keyspaces' rows goes...

How to fix Java JMX RMI Accessible without Credentials

Any idea how to fix this security vulnerability ? Java JMX interface is accessible via following username/password pairs: admin/password admin/admin admin/activemq monitorRole/QED...

How to create a long lived cassandra CqlSession in a Javalin app

I have an app built with Javalin (a simple HTTP framework in Java) that leverages Cassandra as the backend. According to Datastax docs...

No single point of failure with Thingsboard and Cassandra

i already have some experience with Thingsboard setup, but until now i only deployed it using the standalone scenario. One Thingsboard instance with Postgres(hybrid setup) - one Cassandra. What i...

Caused by: com.datastax.oss.driver.api.core.InvalidKeyspaceException: Invalid keyspace mykeyspace in Spring Boot Cassandra

I devised a project with the usage of Spring boot and Cassandra which runs on Docker Container. After I implemented the configuration of Cassandra, I ran the project and it threw an error shown...

Spring Data Cassandra Naming Strategy

Kotlin + Spring Boot Cassandra App is ignoring @Column("column_name") annotations. The below annotation @Column("order_details") val orderDetails: String Is being mapped to orderdetails instead...

Cassandra 4.0 nodes fails to restart

Nodes fail after restart with the error: INFO [Messaging-EventLoop-3-12] 2021-08-17 11:09:07,845 InboundConnectionInitiator.java:464 -...

Maven build Could not resolve dependencies - Failed to collect dependencies at

I am trying to maven build an pom.xml file that I will attached the code below, it takes roughly 6 minutes every build and towards the end it always fails giving the error I will put after the...

spring-data-cassandra-reactive improve performance of ReactiveCrudRepository.save

I have simple showcase with ReactiveCrudRepository, which shows almost 2x difference in insertion speed using ReactiveCrudRepository.save() vs ReactiveCqlOperations.execute() Here is the...

Cassandra log4j Vulnerability exception

We are using apache Cassandra 3.11.7 running on native kubernetes cluster. Is it vulnerable to the log4j security exception?

TypeInformation in Flink to compare the datatypes dynamically

I have a pipeline in a place where data is being sent from Flink to Kafka topic in a JSON format. I was also able to get it from the Kafka topic and was able to get the JSON attributes as well....