Try It Now!

Try It Now!

Here is a funny Kids In The Hall episode from the 90s. Trying to start their car.

Guessing. Trial and error. Testing ridiculous things clearly unrelated to the problem. Funny!

Does it remind you of any tech people that you work with?!

Failure To Do Data Analysis

Databases are all about, data.

So it’s totally bizarre how so many people working with databases never look at the data!

It’s really so fundamental, it’s hard to make a good analogy.  Imagine a tailor making your clothes, but never looked at the fabrics!  Can you think of a better analogy?

I’ve met programmers who have charged ahead and written one thousand lines of code, and have not even looked at either the data in the tables, the input, or the output!

Using the Wrong Object

More Database Design Mistakes To Avoid

Given that you need more information in or from the database, what do you do?

Do you create one of the following?

Defining Recursive Relationships In Lookup Tables!

Another Database Design Mistake to Avoid

Recursive programming is used in a few places in computer science. Most notably in stack processing.  The big picture looks something like:

x program starts  (a)
which calls itself again (b)
which calls itself again (c )

then iteration c finishes
iteration b finishes
iteration a finishes

Recursive relationships are also sometimes used in database design.

The classic example is an organization that has employees.  And managers.   The managers are also employees.

Unfortunately, I’ve seen the recursion pulled out into another table!  A lookup table.

Simple Rule Of Thumb To Determine the Number of Tables In A Relationship

More on Database Design Mistakes to Avoid

Here is my rule of thumb for the number of tables, for each relationship.

Database Design and the Leaning Tower of Pisa

Introducing a number of posts on database design.

A System’s Database Design is like the Foundation to a Building

Database Design is one of the most critical areas in databases.  It is like the foundation to your house.  If you have a bad foundation, you either cannot build at all.  Or, you have to do all kinds of things to compensate for the bad foundation.

A great example of a bad foundation is the leaning tower of Pisa.

Leaning Tower Of Pisa

The tower was not built with the right foundation for the local clay.  Three floors were built, and the tower began to lean because of the weight of the building.  Rather than tearing down the structure and building it again properly, they just decided to wait 100 years for the clay to settle.  And then they built four more floors, parallel to the ground, attempting to compensate for the bad angle of the foundation!   But more problems arose.

For Your Eyes Only

Before I worked with databases, while still in university, I started a wedding photography business which I ran for 11 years.

As I look back at the photography, I really did learn a LOT about business. Marketing: how do I reach those potential customers? Sales. Dealing with customers. And suppliers. Gross margin. Net profit. Cash flow. Operations: altogether, it was about 40 hours of work to shoot a wedding, when you counted up sales, preparation, shooting, and many hours of negative and paper handling to deliver the goods. Capital budgeting; how many more pictures do I need to shoot to make this 1500 dollar lens pay for itself? Break even points. Strategic alliances.

I read a book called Shooting Your Way To A Million, by Richard Sharabura.

There was one chapter called, For Your Eyes Only, where he described how to make a technical portfolio and teach yourself the technical aspects of photography.  Do many test shoots, and put them all in binder.  Different films.  Different lighting conditions, including all the variations in studio lights.  Different exposures.  Different film processing.  Different kinds of objects and people. And always, always, do a lighting test with Polaroid film before shooting.

Why?  When you got into a new situation, you could go back to your reference material for guidance and a starting point.