How to model searchable properties of an entity

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.

To make the things worse, they are searchable, meaning show me all the parts which are blue in color and whose width is less than 10 inches, etc.

Now how do I model my parts table.
If I make, name value pair, them my search will has as many self joins as I have ands in my query.
If I model attributes as columns, then I don't even know all the possible attributes I can have and besides, even if I know them, not all attributes are applicable to all the parts and hence I have really screwed up table

Any help will be appreciated.
Dilip Received on Fri Aug 13 2004 - 08:14:11 CEST