CouchDB is a document-oriented database written in Erlang that addresses a particular “sweet spot” in data storage and retrieval needs. This blog post is an introduction to CouchDB for those of us who have a relational database background.

A CouchDB database doesn’t have tables. It has a collection of documents, stored in a B+Tree. A document is a collection of attributes and values. Values can be atomic, or complex nested structures such as arrays and sub-documents. When you add a document to a database, CouchDB stores it in the B+Tree, indexed by two attributes with special meaning: _id and _rev.

CouchDB lets you store related data together even if it isn’t all the same type of data; you can store documents representing blog posts, users, and comments — all in the same database. This is not as chaotic as it sounds. To get your data back out of CouchDB in sensible ways, you define views over the database. A view stores a …

I had an email after my webinar on NoSQL/SQL for Oracle Development Tools User Group last week (http://www.odtug.com/apex/f?p=500:1:0) from an attendee that was chock full of some questions. I decided to answer them to clarify with this fellow NoSQL and Cloud Systems. I'm pretty happy with my answers. I'd be glad for any thoughts from people about my replies.

Here are my responses (the fellow's name is also Patrick):

Patrick,

You are welcome! Thank you for attending. I put that together a bit hasty but thought it was a good topic to be covering as there are so many organizations that are considering such an architecture.

Patrick Francois wrote:
> Hi,
>
> Thank you for the NoSQL Webinar!
> Not an easy theme. ..kind of "wide open".
> I have recently also tried getting more …

I will be at VLDB 2010 next week.  If anyone on this blog is attending and wants to catch up to discuss start ups and innovation in DB, NoSQL, Big Data etc drop me a line and I will try to meet up.

Welcome to Log Buffer. The weekly review of DBA industry news. Enjoy Log Buffer #199.

Remember if you find a link or interesting blog post that you think Log Buffer should mention, send a note to the editor at Log Buffer and be sure to include the link, and a short note outlining why you think that particular post would be of value to other DBAs, or what you learned from reading it.

And, for inquiries about hosting or editing a future edition of Log Buffer on your own blog, send your query to the Log Buffer coordinator. (Please include the words “Log …

Welcome to Log Buffer, a weekly review of the database industry. This week’s issue Log Buffer #198 is generously published by Sam DeFilippis, who manages Oracle Notes blogs, with latest postings on Oracle GoldenGate.

As always, if you’d like to host your own issue of Log Buffer, simply reach out to the Log Buffer coordinator.
Please enjoy Sam’s issue …

Even though Data warehouse is picking very rapidly in the last year or so, but few companies who are already made a right mark in the right time could not[...]

Log Buffer #197 marks the middle of summer, and the fact that we’re a mere two weeks away from our 200th edition.

To begin this week’s reading, I’d like to highlight two Oracle blogs maintained by Sam J. DeFilippis: Oracle Notes, where he’s recently posted about troubleshooting GoldenGate and positioning a read of Extract/Replicat Trail file or Oracle redo log. Sam volunteered …

Does it matter if the end user knows what the database is?

Recently I got a wonderful view of a database from the end user perspective.

While I was traveling I had found a restaurant where I had decided to let friends who live locally know where I was at. Part way through my food I got a message from a local friend that said "Don't eat there, their food always makes people sick!"

"Always" is a word that I would think would be a little too strong when applied to a restaurant, right?

Nope, the next day I got to feel the full truth of the word.

A couple of days later I am telling some friends about this and a local asked me "Where was this, I want to avoid them." I didn't get asked this question once, I got it asked a dozen times.

I don't know where the place is. Why is that? Because the system I was using lost the entire day worth of my data. I don't know how …

Welcome to Log Buffer, the weekly roundup of database industry news.

For your reading pleasure this week we have Log Buffer #196:

Charles Hooper blogs about an in-depth investigation on what can cause Oracle to ignore a hint.

Doug Burns reminds his readers that there are only two weeks left to …

A short post marks Pythian’s 195th edition of Log Buffer, a blog of blogs encapsulating what’s going on in the world of database administration.

Remember if you find a link or interesting blog post that you think Log Buffer should mention, send a note to the editor at Log Buffer and be sure to include the link, and a short note on why you think that others will want to read it too.

Now on to Log Buffer #195. Alex Gorbachev starts us off with his suggested readings and funnily enough, …