nosql
Why NoSQL is better at “scaling out” than RDBMS?
So I’ve been trying to figure out the real bottom-line when it comes to NoSQL vs RDBMS myself, and always end up with a response that doesn’t quite cut it. In my search there are really 2 primary differences between NoSQL and SQL, with only 1 being a true advantage. ACID vs BASE – NoSQL … Read more
NoSQL Use Case Scenarios or WHEN to use NoSQL [closed]
It really is an “it depends” kinda question. Some general points: NoSQL is typically good for unstructured/”schemaless” data – usually, you don’t need to explicitly define your schema up front and can just include new fields without any ceremony NoSQL typically favours a denormalised schema due to no support for JOINs per the RDBMS world. … Read more
What is the difference between CouchDB and Couchbase?
I think there are some essential differences between CouchDB and Couchbase Server that need to be pointed out. I will not write about the advantages of switching from CouchDB to the Couchbase Server because those are described pretty much everywhere (see The Future of CouchDB by Damien Katz or Couchbase vs. Apache CouchDB by Couchbase). … Read more
Cassandra port usage – how are the ports used?
@Schildmeijer is largely right, however port 7001 is still used when using TLS Encrypted Internode communication So my complete list would be for current versions of Cassandra: 7199 – JMX (was 8080 pre Cassandra 0.8.xx) 7000 – Internode communication (not used if TLS enabled) 7001 – TLS Internode communication (used if TLS enabled) 9160 – … Read more
What does Redis do when it runs out of memory?
If you have virtual memory functionality turned on (EDIT: now deprecated), then Redis starts to store the “not-so-frequently-used” data to disk when memory runs out. If virtual memory in Redis is disabled (the default) and the maxmemory parameter is set (the default), Redis will not use any more memory than maxmemory allows. If you turn … Read more
Is nosql Database good for Online Money Transaction management [closed]
NoSQL databases are there to solve several things, mainly: (buzz) BigData => think TB, PB, etc.. Working with Distributed Systems / datasets => say you have 42 products, so 13 of them will live in Chicago datacenter, 21 in NY’s and another and 8 somewhere in Japan, but once you query against all 42 products, … Read more
MAX(), DISTINCT and group by in Cassandra
With Cassandra you solve these kinds of problems by doing more work when you insert your data — which sounds like it would be slow, but Cassandra is designed for fast writes, and you’re probably going to read the data many more times than you write it so it makes sense when you consider the … Read more