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Database design – SQL vs NOSQL examples

September 29, 2022 by bobbrowning

For the last 50 years there has been one and only one way of designing a database.  SQL Database management systems (DBMS) have been the uncontested standard. (A better name is ‘relational’ because SQL is just the name of the language used to access them, but we will stick with it.)
But things have changed in the last 10-15 years. Databases that disobey relational rules are coming into vogue.  The term NOSQL is used for these non-relational databases (the above chart is work in progress, but I have been looking at these systems.) 
What is the difference between classic databases and this new breed? 

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Handling data consistency in a Document Database

May 17, 2022 by bobbrowning

You know what an invoice looks like.  We have all seen thousands of them – probably too many. But invoices illustrate an interesting problem – and I am not talking about your VAT  return. I am talking about the new kids on the database block – document databases.  An example is MongoDB. These can store all the data for one invoice in a single structured record (called a ‘document’).   

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Lost in MongoDB: Learning to Aggregate

April 5, 2022 by bobbrowning

I am getting to the end of stage one in writing a database driver for MongoDB to use in my Lockdown Project sudsjs.com. All has gone well until I get to totalling up a field in the database. I had to enter the wonderful world of aggregation, which is powerful function-rich and confusing. 

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Why why API?

March 8, 2022 by bobbrowning

I was looking at a page on the IBM website last week when something odd happened. Half the page loaded, then there was a spinning circle (a.k.a. a throbber) for a second or so, then the rest of the page loaded. The page itself is a few paragraphs of very boring text plus a menu. So why the drama with the throbber for a page like that?

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Will NOSQ replace SQL?

March 1, 2022 by bobbrowning


NOSQL databases like MongoDB are making a big splash in the computer industry. But are they set to replace the tried and tested technology of the past fifty years?

Here is my take on it, with a bit of history thrown in.

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Returning to coding 10 years later. A lot has happened.

February 25, 2022 by bobbrowning

As you get older (I’m 80) your brain slows down. This is a well-known fact. The defence against this is to keep it active and learn a new skill.  I tried a new language (Spanish), but it turns out that if you are really bad at languages in your youth you are God-awfully bad in later years. So, I turned to something I did have a talent for – coding. 

As we were stuck indoors anyway, courtesy of Covid, I thought I would update my knowledge of JavaScript, and something called Node. 

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The Power of Yes unfair to Monte Carlo (vs Black-Scholes).

December 14, 2009 by bobbrowning

I went to see The Power of Yes yesterday.  It is a very good explanation of the financial crisis as explained by a playwright – David Hare.  I recommend it – the two hours flew by.  However there was one small item I worried about.  There was a comment about ‘Monte-Carlo methods’ being used by AIG which  got a cheap laugh which I thought unfair.  Monte Carlo methods are not about gambling – they are about minimising risk.

To explain (please bear with me I will get to the point):

The formula used to price a lot of the securities that caused the problem is the Black-Scholes formula – which one of the actors wrote up on a board.  But the statement was made that it ‘predicts’ the future.  Which is doesn’t; unless a statement like ‘if you flip a coin if will be heads 50% of the time’ can be said to be predicting the future.  The Black-Scholes formula just says that if you assume that security prices vary at random then the price in x days time will be within certain limits y and z, except in very exceptional circumstances.

There are two assumptions built into this which are questionable. Continue Reading »

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Key websites for business planning

November 30, 2009 by bobbrowning

Someone just asked me two important questions:

  1. How much traffic should I get on my website
  2. How many of them will buy something

Two good questions to ask when business planning.  A couple of resources that will help you with some numbers.

  1. Statbrain (http://www.statbrain.com/) will give you an idea of traffic levels at competitors sites.   The most commonly used resource is Alexa but I think statbrain gives better numbers.  There are some more here.
  2. The Fireclick index (http://index.fireclick.com/) will give you an idea of conversion rates by industry sector.  Another place to go is Coremetrics.

These are all guesstimates, so don’t expect consistency.

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Can you explain Google wave in 140 characters

November 25, 2009 by bobbrowning

The twittersphere is currently awash with Google Wave offers of invites and requests for invites.  Lots of people want to try it.

Amongst them was this tweet:  “Can someone please inform me on the signifigance of the Google Wave? What exactly is it?”

So your next task if you decide to accept it, is to explain Google wave as a tweet, max 140 characters.   Once I have done that I plan to summarise War and Peace as a tweet – probably easier.

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Google Chrome OS – I don’t like it.

November 20, 2009 by bobbrowning

There is more data about the Chrome OS in a snappy little video and a presentation.  It very much looks as if the new OS from Google is a stripped-down Linux that boots up quickly into a web browser.  It turns your Netbook into a web browsing appliance.

For a lot of people who are only really interested in email, Twitter and Facebook, this is great.  I can definitely see where Google is coming from on this.  It is simple and pretty foolproof for people who don’t really need a PC.

But I don’t like it.

The downside of this simplicity is that it is so limiting.   It locks users into a limited set of applications and excludes the rich set of paid and free software out there.

I think this will be seen as a brilliant way for mobile networks to give away a web browser appliance to sell their broadband.

And I just don’t like it.

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