Write timeout thrown by cassandra datastax driver
While I don’t understand the root cause of this issue, I was able to solve the problem by increasing the timeout value in the conf/cassandra.yaml file. write_request_timeout_in_ms: 20000
datastax
How can I find out which version of Cassandra a specific DSE is running?
Open cqlsh and type show VERSION. This gives all the versions of cqlsh, DSE, Cassandra etc. admin@cqlsh> SELECT cql_version FROM system.local; cql_version ————- 3.4.0 Also, nodetool version shows the Cassandra version
What are the differences between a node, a cluster and a datacenter in a cassandra nosql database?
The hierarchy of elements in Cassandra is: Cluster Data center(s) Rack(s) Server(s) Node (more accurately, a vnode) A Cluster is a collection of Data Centers. A Data Center is a collection of Racks. A Rack is a collection of Servers. A Server contains 256 virtual nodes (or vnodes) by default. A vnode is the data … Read more
How to obtain number of rows in Cassandra table
Yes, you can use COUNT(*). Here’s the documentation. A SELECT expression using COUNT(*) returns the number of rows that matched the query. Alternatively, you can use COUNT(1) to get the same result. Count the number of rows in the users table: SELECT COUNT(*) FROM users;