[Lazarus] OOP - where do you start?

Tony Whyman tony.whyman at mccallumwhyman.com
Fri Jun 26 14:22:31 CEST 2015


As it happens I am doing pretty well the same thing right now - building 
a new application to help me with a requirement capture assignment I am 
starting next week.

This type of application is data driven and that, to me says it all. You 
start by defining the data model eventually ending up with the SQL DDL 
for your database and that in turn drives the application design, with 
typically a form/frame for each of the primary tables.

Of course, pure top down design only ever happens in books or 
programming courses and there will be an element of iteration, going 
back to the data model as the application design progresses, but the 
fundamental is data model first and application second.

Also, I'm working with Firebird/IBX and IBX gives your a lot of design 
time help to build and test the SQL queries. This only works if you have 
a test database available, further emphasising the need to get most of 
the data model in place before building the application.

Tony Whyman
MWA

On 26/06/15 12:30, Graeme Geldenhuys wrote:
> Hi,
>
> Last night I was working on a relatively new project. This got me
> thinking... How do others tackle such a task?
>
> So here is my question:
>
>    When faced with a new database related project, where do you start? Do
> you first design the database schema, then build the BOM (Business
> Objects) accordingly? Or, do you first design the BOM, then design the
> database schema to fit.
>
> Personally, most of my project were started by first creating the
> database schema. Don't ask me why, that is just what I did. Maybe it was
> because many of the tools I use, can write much of the boiler plate code
> for me, and they do that by querying a database structure. But I've been
> thinking that with my next project, I'm going to start with the BOM
> first, and see how it goes. I'm assuming the end result should be the
> same, no matter which part I tackled first.
>
> What's your thoughts?
>
> Regards,
>    - Graeme -
>





More information about the Lazarus mailing list