Questions tagged [cassandra]
Apache Cassandra is a highly scalable, eventually consistent, distributed, structured row store. Questions about Cassandra server administration should be asked on https://dba.stackexchange.com/questions/tagged/cassandra .
cassandra
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How to Design Uber Location Tracking [closed]
Dear Stack Experts,
I was asked in an interview recently to design ride/driver location tracking feature of Uber. I could come up with simple design constituting of data bases i.e., Cassandra(Write ...
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10
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Debezium Cassandra Connector not working in Docker container
I am trying to use the Debezium Cassandra connector in a Docker container using the debezium/connect image. However, the Cassandra connector is not showing up in the list of available connectors.
I ...
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1
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Cassandra CQL where clause parentheses Issue
SELECT
*
FROM ALARM_HISTORY
WHERE DOMAIN IN ('BAREMETAL','CLOUD','CORE','FIBER','INFRA','PLATFORM','RAN','SECURITY','TRANSPORT')
AND ((actual_severity = 'MAJOR') AND (technology = 'LTE'))
ALLOW ...
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1
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How to Print Humongous Allocations in a Java Program Without Using GC Logs?
I'm currently working on a Java application that makes use of humongous allocations and regions. Typically, I would monitor these allocations and regions using the GC (Garbage Collection) logs. ...
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Cassandra multi-region clusters interconnect
I faced with problem due to connect two cassandra clusters placed in different datacenters. Each datacenter have public ip - lets assume there are 111.111.111.111 and 222.222.222.222. Cassandra nodes ...
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cassandra 4 with SSL jmx thrown error in jConsole
I am using Cassandra 4 and have enabled SSL.
To connect to JMX, I added the following options in the cassandra-env.sh and started Cassandra
JVM_OPTS="$JVM_OPTS -Dcom.sun.management.jmxremote.ssl=...
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1
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39
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Why OutOfMem error for Cassandra pod on Kubernetes despite sufficient RAM in worker node?
I am running a cassandra pod on a Kubernetes worker node named kworker4 which has 16 GB RAM and no other pod is running in that worker node. I am using bitnami/cassandra.
The memory and CPU usage is ...
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9
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Writes on Cassandra adds upto Bytes unrepaired
For testing purpose, I am using NoSQLBench to load the data on Cassandra 5.x. Its a 3 nodes cluster. I've noticed that when rampup(load) phase completes, the size of Bytes unrepaired reaches to the ...
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1
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Query fails to retrieve data, getting "Failed to get variables", "select query processing: line 1:34 mismatched character 'd' expecting '$'"
I have an issue. I want to visualize my data in Cassandra with Grafana. I made the connection and created a dashboard. I created 2 variables in this dashboard. These are devices and entity. I wrote ...
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2
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QUORUM reads fail when one of two DCs are down
We have 2 DCs with RF=3 in this cluster: DC1 3 nodes DC2 3 nodes
The customer has requested that when DC2 goes down (all 3 nodes down), they want to keep the cluster working without any quorum issues.
...
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Create Statement in Spring Data Cassandra
How can I create a Statement using Spring Data Cassandra in a way that spring would handle type conversion as well?
If I have a simple query with simple types, I could write something like this:
...
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Cassandra 4.1 read timeout for a simple use case
I am running into read timeout problems which I would not expect.
3 nodes on commodity hardware and on my home network, replication factor 2
one simple keystore and table:
CREATE KEYSPACE IF NOT ...
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26
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Does updating a frozen column generate a tombstone? [migrated]
I was planning to change my column from nonfrozen to frozen. I would like to know if there are any guidelines for updating the frozen column with respect to tombstone generation. In some blogs it is ...
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Unable to start cqlsh on because of Python 3.12.3, getting "ModuleNotFoundError: No module named 'six.moves'" [duplicate]
Virtual machine and docker not practical for my application because I need to be able to save the Cassandra database locally on a regular basis (incremental backup is true)
Does anyone have a ...
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32
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Append a json to a key which is a array in a existing json column
I have a JSON {"user": "test"} and I have an existing JSON column userjson which is {"uid": "1", "info": []} in my cassandra database.
I want to ...
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