Should you go Beyond Relational Databases? | Think Vitamin
http://thinkvitamin.com/dev/should-you-go-beyond-relational-databases/

Relational databases, such as MySQL, PostgreSQL and various commercial products, have served us well for many years. Lately, however, there has been a lot of discussion on whether the relational model is reaching the end of its life-span, and what may come after it.

Alternatives to SQL dbs - document, key-value, graph databases

No to SQL? Anti-database movement gains steam

The meet-up in San Francisco last month had a whiff of revolution about it, like a latter-day techie version of the American Patriots planning the Boston Tea Party. The inaugural get-together of the burgeoning NoSQL community crammed 150 attendees into a meeting room at CBS Interactive. Like the Patriots, who rebelled against Britain's heavy taxes, NoSQLers came to share how they had overthrown the tyranny of slow, expensive relational databases in favor of more efficient and cheaper ways of managing data. "Relational databases give you too much. They force you to twist your object data to fit a RDBMS [relational database management system]," said Jon Travis, principal engineer at Java toolmaker SpringSource, one of the 10 presenters at the NoSQL confab (PDF). NoSQL-based alternatives "just give you what you need," Travis said. Open source rises up The movement's chief champions are Web and Java developers, many of whom learned to get by at their cash-strapped startups without Ora

The meet-up in San Francisco last month had a whiff of revolution about it, like a latter-day techie version of the American Patriots planning the Boston Tea Party.

piece on an alternative approach to data management

Cassandra is a hybrid non-relational database in the same class as Google's BigTable. It is more featureful than a key/value store like Dynomite, but supports fewer query types than a document store like MongoDB. Cassandra was started by Facebook and later transferred to the open-source community. It is an ideal runtime database for web-scale domains like social networks.

As a Web developer it's always a good idea to know what the current practices are in the industry even if they seem a bit too crazy to adopt…yet.

bit on why non-SQL dbs are used in social networking sites

Really interesting article about mongoDB and about the installation procedure

"MongoDB can be thought of as the goodness that erupts when a traditional key-value store collides with a relational database management system, mixing their essences into something that’s not quite either, but rather something novel and fascinating. -- MongoDB support is available in many languages, making it a good choice for a system that has to work in a polyglot environment; all of the major languages have support."

Presentation on how googleapps datastore implements filtering and sorting on top of bigtable. Basically, all queries are translated to bigtable prefix scans or range scans, without needing any in-memory postprocessing, all rows returned from the scan are relevant to, and in order, for the query. There's a built-in 'single property index' (or two actually: one asc and one desc) which can obviously be used for single-property searches, but also for queries consisting of only equals clauses, by doing multiple range scans and taking the intersection (not sure at which level this happens). More complex queries need specific pre-defined indexes. Index tables only have keys, no columns with values. Indexes are updated synchronously, so everything stays consistent (at the cost of contention problems?). Some mention of string-byte considerations when doing range queries. No fulltext queries. Ends with some talk on transactions.

キーバリューストアの解説 「CAP定理」では、分散システムで以下の3つを同時に保証することは不可能であることが示されています。 * データの整合性（Consistency） * データの可用性（Availability） * データの分散化（Partition-tolerance）

>RDBとは別の、クラウド時代のデータベースとして注目を浴びている「分散Key-Valueストア」。その本命ともいえる、Googleの数々のサービスの基盤技術「Bigtable」について徹底解説 どうかなあ…

Bigtable, SimpleDB, Tokyo Tyrant

Introductory blog post about the Cassandra data model.