Shamil's Blog. Software Engineering Processes, Android, CI, Devops.

Hibernate.org's 'hibernate tools' redirects to jboss downloads, where "Stand-alone Installer" link is '404 not found'. Cool. Here it is: http://tools.jboss.org/downloads/devstudio/neon/10.2.0.GA.html#direct_download

Several hours after registering at Neocities I've received confirmation email from Microsoft:

To finish setting up this Microsoft account, 
we just need to make sure this email address is yours.

The thing is that I'm pretty sure I did not create any microsoft emails by myself and this email is a secondary one and I do not use it frequently.

So be careful when using Neocities as they could have some data leak.

Labels: hacking, neocities, spam

Based on Datastax intro.

1. Distributed computation engine (aim on low latency)
2. Could be used both batch-mode or interactive
3. In-memory
4. Faster than Hadoop
5. Fault-tolerance out-of-the box

Labels: apache spark, software architecture, software engineering, spark

These notes are based on short intro.

1. cassandra has thing called "partitioning key" which is a part of the _primary key_
PK -> consistency hashing function -> value determines which Bucket (range of Hashes) it fits into -> which node we need to talk to

2. CAP theorem tradeoffs. Cassandra is Highly Available (Availability) and Partition Tolerant (Partitioning)

3. Replication. RF = 3 - factor of replication.

4. Consistency level (how many confirmations of actual nodes has written data): { All, Quorum, One }. Also can have a modifier "Local" in case of multiple data centers. We can write to different DC which could be one for OLAP one for OLTP (for different queries does not impact performance each other)

5. CL - per query; RF - per keyspace

Labels: apache cassandra, big data, cassandra, software architecture

Here's a great post on what is business logics and should we use Stored Procedures for this kind of stuff.

Labels: business logics, data logics, engineering, software, software engineering