You can use the timeuuid functions now() and dateof() (or in later versions of Cassandra, toTimestamp()), e.g., INSERT INTO TEST (ID, NAME, VALUE, LAST_MODIFIED_DATE) VALUES (‘2’, ‘elephant’, ‘SOME_VALUE’, dateof(now())); The now function takes no arguments and generates a new unique timeuuid (at the time where the statement using it is executed). The dateOf function takes … Read more
Short summary: Replication factor describes how many copies of your data exist. Consistency level describes the behavior seen by the client. Perhaps there’s a better way to categorize these. As an example, you can have a replication factor of 2. When you write, two copies will always be stored, assuming enough nodes are up. When … Read more
Dbeaver in its free enterprise version (not open source) is good GUI client for Cassandra. No need of installation. Its portable. Also this client supports more than 20 databases. Community Edition of Dbeaver doesn’t have support for Cassandra, but we can use third party drivers for like Cdata to connect. Try the following GUI client … Read more
You could use “child process” module of nodejs to execute any shell commands or scripts with in nodejs. Let me show you with an example, I am running a shell script(hi.sh) with in nodejs. hi.sh echo “Hi There!” node_program.js const { exec } = require(‘child_process’); var yourscript = exec(‘sh hi.sh’, (error, stdout, stderr) => { … Read more
text is just an alias for varchar! The documentation: Using cql3 – Datastax CQL commands – Datastax Documentation on Datatypes in CQL – Datastax CQL3 Documentation – Apache EDIT Here’s the link to the C* 1.2 docs. The text vs varchar info is still the same, however this document contains some extra datatypes. EDIT v2 … Read more
Don’t let the spatial scale (1000+ devices) mislead you as to the computational and/or storage scale. A few dozen 35-byte inserts per second is a trivial workload for any mainstream DBMS, even running on low-end hardware. Likewise, 142 million records per month is only on the order of 1~10 gigabytes of storage per month, without … Read more
From cqlsh execute describe tables;
CouchDB is a document store. You put documents (JSON objects) in it and define views (indexes) over them. The objects can be arbitrarily complex with potentially deep structure. Further, they are not constrained to following some consistent schema. Cassandra is a ragged-table key-value store. It just stores rows, each of which has a set of … Read more
If you take a look at the Readme file at Apache Cassandra git repo, it says that, Cassandra is a partitioned row store. Rows are organized into tables with a required primary key. Partitioning means that Cassandra can distribute your data across multiple machines in an application-transparent matter. Cassandra will automatically repartition as machines are … Read more