Re: [PHP] Web dev, DB and "proper db design".

Tony Marston wrote:
>> Certainly in some instances then managing everything in code makes sense.
>> Cross database working for instance. So everything works the same for each
>> engine. But the main advantage of adding constraints in the database is that
>> it protects the foreign entries from being deleted while they are still in
>> use. One of the problems I end up having to recover is where a hickup in the
>> PHP or user side of things has deleted an entry, or more usually the whole
>> table! In this case a properly implemented constraint would have prevented the
>> problem. While using a constraint to manage the deletion of detail elements
>> has a place in reducing traffic between program and database, the protection
>> of detail elements is the more useful reason for maintaining them.
>
> In my framework I define relationships and any constraints in my data
> dictionary, and these are enforced by a standard module in the framework. This
> means that any RESTRICTED constraints can be detected in the code without
> executing a DELETE and having it abort.

My own database management framework pre-dates PHP switching from dBase 
originally, to Interbase and then Firebird as it was open sourced (just as we 
had paid for a large number of Interbase licenses :( ). So I've grown up using 
the tools in the database, but have to back pedal some of the time where a cross 
database solution is required. I'm much more comfortable with getting the 
database to manage things and will often drop triggers in rather than coding 
that in PHP. So "proper db design"is probably still geared around what we are 
used to rather than any had and fast rules?

-- 
Lester Caine - G8HFL
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