Questions tagged [cassandra]

Apache Cassandra is an open source distributed database management system. It is designed to handle very large amounts of data spread out across many commodity servers while providing a highly available service with no single point of failure. It is a NoSQL solution.

Filter by
Sorted by
Tagged with
1
vote
1answer
991 views

Cassandra: memtable_offheap_space_in_mb and memtable_cleanup_threshold

I use C* v2.1.2 do write only workload (into one column family) and experiment with offheap-objects memtable space. I set parameters to: memtable_offheap_space_in_mb = 51200 # 50Gb ...
1
vote
1answer
634 views

Date model for commenting system stored in a key-value NoSQL DB?

I'm trying to leverage Cassandra's strong support for time series data to build a commenting system. So far I'm thinking that each row would be a particular topic, and each comment would be a new ...
1
vote
1answer
4k views

Cassandra: Request did not complete within rpc_timeout

i was working with Cassandra 1.2.4 probably, after restoring some key-space when i tried to query in a key-space it gave me Request did not complete within rpc_timeout so i checked system.log & ...
1
vote
0answers
15 views

Elassandra data modeling

In Cassandra, everyone always stresses how important data modeling is, and rightfully so. However, when using Elassandra, we have Elasticsearch baked in. How does should change how we think about ...
1
vote
1answer
25 views

Read from partition in local cassandra node only

I'm aware that I can read from any cassandra node and it acts as coordinator to read from the node containing a specific partition, but can I read data only from the partition which is on the node I'm ...
1
vote
0answers
40 views

Cassandra not returning the row of the specified primary key

First of all, my table is structured like this: CREATE TABLE timeseries_data.test_data ( date timestamp PRIMARY KEY, data1 float, data2 float ) WITH bloom_filter_fp_chance = 0.01 AND ...
1
vote
1answer
124 views

What happens if one DC goes down in Cassandra multi DC setup?

We have a Cassandra multi DC setup with 3 nodes in each DC, enabled with NetworkTopologyStrategy and RF 3. The java client interacts with Cassandra cluster using read and write consistency as ...
1
vote
0answers
16 views

compaction strategies and high performance storage

My apologies for this being a somewhat newbie question. However, my understanding of Cassandra is that is use three different compaction strategies: are these tunable, or is this area a black box, i....
1
vote
0answers
79 views

Cassandra slow read performance after migrating to new AWS instance class

Cluster of 3 cassandra nodes as a dev environment. Used to run in AWS on i3.2xlarge; migrated as a test to i3en.2xlarge to evaluate for later migrating production cluster to. When running cassandra-...
1
vote
0answers
17 views

Cassandra multi data centre cluster configuration [closed]

We are decided to use "cassandra" as a database and now want to go with cluster with two datacenters DC1 & DC2. This DC2 is for backup purpose and it is replica of DC1. Initially we are expecting ...
1
vote
0answers
179 views

Why getting Error accessing Cassandra with DataStax ODBC Driver?

We are using Cassandra 2.2.11, and trying to configure DataStax ODBC driver. We are getting the following error message: SQLSTATE: HY000[DataStax][CassandraODBC] (10) Error while executing a query ...
1
vote
2answers
2k views

Cassandra querying without full primary key

As far as I understand there are no secondary indices with multiple columns, only single columns. So how do I solve the index problem I'm having? This is my table: CREATE TABLE IF NOT EXISTS logstv....
1
vote
0answers
174 views

Cassandra pool warning displaying continuously

I am using the Cassandra driver for python in Spyder. I am trying to fetch some data from Cassandra table. Here is my code: from cassandra.cluster import Cluster cluster=Cluster(['some_ip']) session=...
1
vote
0answers
417 views

Error on cassandra-3.11.3-1.noarch centos7

I've a cluster consisting of 5 cassandra nodes. The cassandra version used is cassandra-3.11.3-1.noarch The keyspace strategy and is defined as follows: CREATE KEYSPACE my_keyspace WITH ...
1
vote
0answers
31 views

Kill client connection to Cassandra instance

Not able to go to find any documentation on how to kill a client connection to remote Cassandra I will instance .. as a DBA at the server end? Seems like an easy task but why no mention of this in ...
1
vote
1answer
271 views

Cassandra nodes are not equal

We have two nodes. Node1 was down for a long time. During this time Node2 raised 1 TB capacity when Node1 has 100 GB. We tried to repair Node1 with nodetool repair but nothing changed. After that we ...
1
vote
2answers
152 views

password expire duration and maximum invalid login attempts

how to set password expire duration and maximum invalid login attempts for user under Cassandra DB ? for example user test tried to login with incorrect password 5 times , that should should get ...
1
vote
0answers
412 views

List Roles on cassandra getting NoHostAvailable on one DataCentre

I have a 2 DC cluster, 'main' and 'bi' with a replication factor of 3 and a NetworkTopologyStrategy. When I call LIST HOSTS; in cqlsh, my bi datacentre lists all the roles appropriately, but I get a ...
1
vote
0answers
381 views

Increase timeout for cassandra native transport threads?

From the Cassandra documentation here native_transport_max_threads The maximum number of thread handling requests. Similar to rpc_max_threads, but this property differs as follows: The ...
1
vote
0answers
129 views

Is my schema for a Discussion forum using Cassandra optimum or has a scope for improvement?

I am designing a Discussion Forum for my app which has following primary objects: Image Video Text Audio The owner can start a discussion in context of any of the above object. Based on user ...
1
vote
0answers
60 views

Is it possible to have a partition to distribute transaction load horizontally in SQL Server 2016?

In Cassandra, you can have a partition key to align partitions to particular server nodes. My understanding is that you can distribute transactional responsibility horizontally in SQL Server 2016 (...
1
vote
0answers
47 views

What type of primary key we need to use for specific length of bits in Cassandra?

I want to know in which situations which type of primary key I need to use. Situations: 1. If I need 64 bit key than is bigint is the best for it? If I will chose text type will performance will be ...
1
vote
0answers
314 views

Why restore a single node of a cluster?

We were reviewing the restore documentation for Cassandra here, and noted it made the following distinction between restoring a single node or an entire cluster: If restoring a single node, you ...
1
vote
1answer
273 views

Upgrading Cassandra [duplicate]

my Cassandra version is 1.2.4 and i'm trying to upgrade it to 2.0.5 and i know that in the first part i have to upgrade it to 1.0.14 and after that try to upgrade it to the 2.0.5 , when I try to run ...
0
votes
2answers
2k views

Commercial database systems versus open source database systems [closed]

Can anyone tell me what are the reasons for buying a commercial database system and not using an open-source free version? The reason for my question is that: Commercial systems cost upwards of 10....
0
votes
1answer
2k views

A good dataset to experiment NoSQL databases [closed]

I need to do some experiments in HBase and Cassandra and to do that I need an adequate dataset. The dataset I'm looking for has to be large enough (i.e. more than 2GB) and the data in it has to be ...
0
votes
1answer
40 views

What things we should consider when configuring Cassandra Cluster?

I'm new to Cassandra, so wanted to understand what basic things we should consider when are we going to configure Cassandra cluster in on or multiple database centers? Thanks!
0
votes
1answer
1k views

ConnectException: 'Connection refused'

My node worked normally, and I could use nodetool status normally, but when I changed endpoint_snitch to Ec2Snitch I started getting the error: nodetool: Failed to connect to '127.0.0.1:7199' - ...
0
votes
1answer
324 views

How to set Cassandra volumes?

I have started a Cassandra server using Bitnami AMI, I have attached volumes to the EC2 instance, but how would I set Cassandra to use the attached volume?
0
votes
1answer
1k views

Cassandra nodetool repair parallelism: “parallel” versus “dc_parallel”

If I run nodetool repair --full I see settings like this: repairing keyspace some_keyspace with repair options (parallelism: parallel, primary range: false, incremental: false, job threads: 1, ...
0
votes
1answer
156 views

How Wide-columns databases achieve dynamic columns on the storage layout? [closed]

As known, in relational databases, when adding a new column, data must be reallocated (https://stackoverflow.com/questions/463677/alter-table-without-locking-the-table) to maintain a single row ...
0
votes
1answer
37 views

Data replication in Cassandra

We have a 5 node cluster in Cassandra in which we have created a keyspace with RF=3. After creating a column-family(table) when we insert the data into the same, it is getting replicated in all the ...
0
votes
2answers
59 views

Cassandra Cluster storage

I want to try out Cassandra Cluster. My main question is about scalability. Every node in a Cassandra cluster has the same copy of data. So when I have in total 1 TB and have 5 nodes -> 5TB. This at ...
0
votes
2answers
366 views

Handling read conflict in cassandra?

Say we have three nodes(simple replica no sharding) i.e. N1,N2 and N3 with replication factor as 3. As read and write request can go to any node, Say Request write request(to update the same ...
0
votes
1answer
61 views

best way to retrieve data using multiple parameters in Cassandra?

I have created a table that contains the userid, the content that they posted on their newsfeed, the date of when they posted it, and a primary key(I am using nodejs) my first shot at retrieving the ...
0
votes
1answer
56 views

Cassandra - reinserting a node

I had to remove a cassandra dead node on a hurry (because an important script with a truncate query wouldn't work due to consistency level reasons -- any thoughts on that would be nice too). Anyway, ...
0
votes
1answer
2k views

Why doesn't nodetool work on my Cassandra Cluster?

I have never been able to get nodetool to operate correctly to give me information about my cluster. We have a simple 3-node cluster of Cassandra 3.11.1 nodes running under CentOS 7.3 -- using the ...
0
votes
1answer
1k views

Cassandra Consistency Level

I have 3 virtual Cassandra nodes cluster. Node1, Node2 & Node3. I have written a small python code to bulk load data into it. 1st time only 2 nodes out of three are available online, Node1 & ...
0
votes
1answer
180 views

MyRocks vs Cassandra data size

Both MyRocks (MySql) and Cassandra uses LSM architecture to store their data. So I have populated around 5 million rows in MySql with MyRocks as storage engine and also in Cassandra. In Cassandra it ...
0
votes
1answer
535 views

What is an efficient storage method to store Graph Data from GraphX (Spark)?

I generate graph data using Spark's GraphX library and I need an efficient way to store graph data. I have access to Apache Cassandra and ideally I want to store the graph data in there but the issue ...
0
votes
1answer
297 views

can I set a MAX Limit to a BIGINT cassandra's data type?

can I set a MAX Limit to a BIGINT cassandra data type? this is my first step in cassandra db. for example: bigint(10) just like in mysql?
0
votes
1answer
94 views

customize permission in Cassandra

i want to grant user update permission in Table and deny delete permission for this user. Is there any way to accomplish this?
0
votes
1answer
176 views

how to disable delete in replication Cassandra datastax

my previous scenario i used Sql server one instance in amazon for live and the second in local network for archiving by disable delete in replication can i do this in Cassandra or what best ...
0
votes
2answers
2k views

Cassandra - save file

I'm new with Cassandra, and even more - I never have such task for habitual RDMS systems, like MariaDB or Oracle. So, how can I store file in to Cassandra's table? Preferably using Python-driver, but ...
0
votes
1answer
251 views

Cassandra with Hadoop

Cassandra uses Cassandra File System (CFS) and Hadoop uses Hadoop Distributed File System (HDFS) I'm already using Pig over HDFS and i would like to install Cassandra. Having additional servers for ...
0
votes
0answers
19 views

Choosing database type and schema for rental availability

I'm looking at what type of database and schema is best to use for product rental availability. The requirements are simply that it needs to cater for high writes and low reads. So I've been pushed ...
0
votes
0answers
14 views

Sigle sign on solution for Cassandra with Keycloak

Please suggest if there are possible solution of itegrating SSO for Cassandra with keycloak. I have searched for blogs for keyclock integration with cassandra. I couldn't find how to integrate these ...
0
votes
1answer
29 views

Cassandra security - private IPs with some VPN solution or public IPs and open ports?

there are many different solutions to secure a cassandra cluster. One of them is to enter public IPs and open the 7000/9042 port on each sever. Another one is to have everything in a private network ...
0
votes
0answers
20 views

How to use Apache Calcite (+ Cassandra) through NodeJS

When reading the documentation for Apache Calcite, it seemed astonishingly attractive as being part of a team currently porting an SQL application into Cassandra's popular CQL. After some more digging,...
0
votes
1answer
170 views

Cassandra goes down after some some days

I am running cassandra in 3 node cluster with replication factor 3. It was working fine for 2 days and all of a sudden it went down. I am beginner to cassandra database. I went through documentation ...