Re: How to model searchable properties of an entity

In message <4b45d3ad.0408200745.4983d97a_at_posting.google.com>, Neo <neo55592_at_hotmail.com> writes
>> Let us say I have Part# and it has very large number of flexible
>> attributes defined by the user, such as color, width, height, etc...
>> Depending on Part number, these attributes may change.
>
>There is an inherent mismatch between tables containing rows with
>uniform number of columns and "flexible attributes defined by the
>user". Its like asking how to fit a circle in a square. The solution
>will always be less than ideal.

That's true, but although it is possible to design a relational database subject to this problem I've never felt the need to design one. There are two simple solutions; nulls and sub-entities. It is quite possible to build relational databases using one or both of those solutions.

Although either method may be less than ideal (in different ways, depending what your notion of ideal might be) they do work reasonably well.

-- 
Bernard Peek
London, UK. DBA, Manager, Trainer & Author. Will work for money.