Cassandra 2.0 Architecture

In this article, I will cover various key structures that makes up Cassandra. We will also see what structure resides in memory and what resides on disk.

In next article, I will give an overview of various key components that uses these structure for successfully running Cassandra. Further articles will cover more details about each structure/components in details

Cassandra Node Architecture:

Cassandra is a cluster software. Meaning, it has to be installed/deployed on multiple servers (more...)

Apache Cassandra – NoSQL storage solution

These days I am exploring another storage solution – Cassandra.

Apache Cassandra datastore was originally developed by Facebook as open source NoSQL data storage system. Its actually based on Amazon’s dynamoDB database. Apache Cassandra is an open source distributed database management system designed to handle large amounts of data across many commodity servers, providing high availability with no single point of failure. Cassandra offers robust support for clusters spanning multiple datacenters, with asynchronous masterless replication allowing low latency operations (more...)

Eventual Consistency is NOT a violation of the relational model (says C. J. Date)

C. J. Date was kind enough to comment on my article in the last issue (February 2015) of the NoCOUG Journal (see The Rise and Fall of the NoSQL Empire ). The full text of his remarks will be published in the next issue (May 2015). Here’s a sneak preview: First, to say that a database (distributed or otherwise) is consistent merely means, formally speaking, that the database conforms to all stated integrity constraints. Now, (more...)

The Rise and Fall of the NoSQL Empire (2007–2013)

The NoSQL camp put performance, scalability, and reliability front and center but lost the opportunity to take the relational model to the next level because—just like the relational camp—it mistakenly believed that normalization dictates physical storage choices, that non-relational APIs are forbidden by the relational model, and that “relational” is synonymous with ACID (Atomicity, Consistency, Isolation, and Durability). The NoSQL camp created a number of innovations: functional segmentation, sharding, replication, eventual consistency, and schemaless design. (more...)

NoSQL Joke and DBA humor

Once, a very long time ago, I told an old joke about SQL and it was a huge success (not really).
This week I heard a joke that is slightly related to that joke and it made me giggle for a couple of minutes.
Those who know me, knows that I really like to hear jokes but I’m really terrible at telling them – but let’s go for it anyway.

2 DBAs NoSQL walk into (more...)

Introduction to MongoDB Security

View it on my new blog Last week at the Paris MUG, I had a quick chat about security and MongoDB, and I have decided to create this post that explains how to configure out of the box security available in MongoDB. You can find all information about MongoDB Security in following documentation chapter: http://docs.mongodb.org/manual/security/ In this post, I won't go into the detail about

Moving My Beers From Couchbase to MongoDB

See it on my new blog : here Few days ago I have posted a joke on Twitter Moving my Java from Couchbase to MongoDB pic.twitter.com/Wnn3pXfMGi — Tugdual Grall (@tgrall) January 26, 2015 So I decided to move it from a simple picture to a real project. Let’s look at the two phases of this so called project: Moving the data from Couchbase to MongoDB Updating the application code to use

Thoughts and notes, Thanksgiving weekend 2014

I’m taking a few weeks defocused from work, as a kind of grandpaternity leave. That said, the venue for my Dances of Infant Calming is a small-but-nice apartment in San Francisco, so a certain amount of thinking about tech industries is inevitable. I even found time last Tuesday to meet or speak with my clients at WibiData, MemSQL, Cloudera, Citus Data, and MongoDB. And thus:

1. I’ve been sloppy in my terminology around “geo-distribution”, in (more...)

Openworld 2014

Oracle OpenWorld

Are you going to Oracle OpenWorld 2014? I am, and I hope to see you there! As you probably know, OpenWorld is a humongous event with tens of thousands of people in attendance and some amazing presentations. Why, I even hear Oracle’s new CTO might be there. I wonder if he has anything to talk about?

This year we’ll have a ton of activity at the Delphix booth. You can check out the speaking schedule, (more...)

21st Century DBMS success and failure

As part of my series on the keys to and likelihood of success, I outlined some examples from the DBMS industry. The list turned out too long for a single post, so I split it up by millennia. The part on 20th Century DBMS success and failure went up Friday; in this one I’ll cover more recent events, organized in line with the original overview post. Categories addressed will include analytic RDBMS (including data (more...)

Editor’s Choice award at ODTUG Kscope14: NoSQL and Big Data for the Oracle Professional

My paper on NoSQL and Big Data won the Editor’s Choice award at ODTUG Kscope14. Here are some key points from the paper: The relational camp made serious mistakes that limited the performance and usefulness of the relational model. NoSQL is based on the incorrect premise that tables in the relational model must be mapped to […]

MongoDB is growing up

I caught up with my clients at MongoDB to discuss the recent MongoDB 2.6, along with some new statements of direction. The biggest takeaway is that the MongoDB product, along with the associated MMS (MongoDB Management Service), is growing up. Aspects include:

  • An actual automation and management user interface, as opposed to the current management style, which is almost entirely via scripts (except for the monitoring UI).
    • That’s scheduled for public beta in May, (more...)

NoSQL vs. NewSQL vs. traditional RDBMS

I frequently am asked questions that boil down to:

  • When should one use NoSQL?
  • When should one use a new SQL product (NewSQL or otherwise)?
  • When should one use a traditional RDBMS (most likely Oracle, DB2, or SQL Server)?

The details vary with context — e.g. sometimes MySQL is a traditional RDBMS and sometimes it is a new kid — but the general class of questions keeps coming. And that’s just for short-request use (more...)

ADF UI with MongoDB for persistence

The sample application (JDeveloper 12c / 12.1.2) can be downloaded from here.
This is a simple ADF application whose underlying business service implementation uses MongoDB for persistence.
The application allows create & update operations on a one-to-many data model (Department-Employees)

As shown in the screenshot below, you can (more...)

RDBMS and their bundle-mates

Relational DBMS used to be fairly straightforward product suites, which boiled down to:

  • A big SQL interpreter.
  • A bunch of administrative and operational tools.
  • Some very optional add-ons, often including an application development tool.

Now, however, most RDBMS are sold as part of something bigger.

How to implement Document Versioning with Couchbase

Introduction Developers are often asking me how to "version" documents with Couchbase 2.0. The short answer is: the clients and server do not expose such feature, but it is quite easy to implement. In this article I will use a basic approach, and you will be able to extend (more...)

SQL to NoSQL : Copy your data from MySQL to Couchbase

TL;DR: Look at the project on Github. Introduction During my last interactions with the Couchbase community, I had the question how can I easily import my data from my current database into Couchbase. And my answer was always the same: Take an ETL such as Talend to do it Just write a (more...)

Six months as Technical Evangelist at Couchbase

Already 6 months! Already 6 months that I have joined Couchbase as Technical Evangelist. This is a good opportunity to take some time to look back. So first of all what is a Developer/Technical Evangelist? Hmm it depends of each company/product, but let me tell you what it is for (more...)

Screencast : Fun with Couchbase, MapReduce and Twitter

I have created this simple screencast to show how you can, using Couchbase do some realtime analysis based on Twitter feed. The key steps of this demonstration are Inject Tweets using a simple program available on my Github Couchbase-Twitter-Injector Create views to index and query the Tweets by User name Tags (more...)

NoSQL and Oracle, Sex and Marriage

At last week’s Dallas Oracle Users Group meeting, an Oracle DBA asked me, “With all the new database alternatives out there today, like all these open source NoSQL databases, would you recommend for us to learn some of those?”

I told him I had a theory about how (more...)