Re: My honours project - databases using dynamically attached entity-properties

Josh Berkus wrote:
> Amdrew,
> 
>> I have yet to encounter one, but
>> Josh has more experience, and more varied experience than I do. To me,
>> EAV is a perfect example of ignoring the YAGNI principal.
> 
> I've done plenty of applications where part of the specification for the 
> application was "User Defined Fields" allowing the users to customize the 
> data structure at runtime.  This is a very, very common thing; of the 15 
> or so commercial applications I implemented from scratch as a consultant 
> probably 10 of them had it.

Just to add a note from YAJ, custom fields are unfortunately a
requirement in most apps I have seen, from a CMS to Quickbooks. The
reality is, you don't know everything the person wants to know about a
particular set of data.

Joshua D. Drake


> 
> I really don't see any way you could implement UDFs other than EAV that 
> wouldn't be immensely awkward, or result in executing DDL at runtime.
> 


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