This is a very interesting talk by Jonathan Ellis on database scalability. He designed and implemented multi-petabyte storage for Mozy and is currently the project chair for Apache Cassandra.

What every developer should know about database scalability, PyCon 2010
View more presentations from jbellis.

Scalability is not improving latency, but increasing throughput
But overall performance shouldn’t degrade
Throw [...]

Cassandra is the only NOSQL datastore I’m aware of, which is scalable, distributed, self replicating, eventually consistent, schema-less key-value store running on java which doesn’t have a single point of failure. HBase could also match most of these requirements, but Cassandra is easier to manage due to its tiny footprint.
The one thing Cassandra doesn’t do [...]

Hive is a data warehouse infrastructure built over Hadoop. It provides tools to enable easy data ETL, a mechanism to put structures on the data, and the capability to querying and analysis of large data sets stored in Hadoop files. Hive defines a simple SQL-like query language, called QL, that enables users familiar with SQL [...]

Jonathan Ellis’ started up a storm when he posted an entry about CouchDB about 6 months ago. He questioned some of CouchDB’s claims and made an attempt to warn users who don’t understand practical issues around CoughDB very well.
After reading his post and some comments, it looked like he was specifically concerned about [...]

I heard a great set of Google App engine datastore related talks at the google I/O conference. I think this is one of the best out talks I heard which is now on Youtube. You should watch it if you are working with or planning to work with Google App Engine in the near future. [...]