Partial custom fields design document

[Gervase Markham]

Joel Peshkin wrote:
> The problem with that particular item is that it is a terrible plan.  
> Having custom fields come and go from the UI on a per-product basis is 
> great.  Having them come and go from the DB on a per-product basis is a 
> recipe for dataloss.  Once a bug has a custom field, it should be stuck 
> with that field forever, even if it is moved to a product where that 
> field is not supported and then back again.

Sure - that's a very good point. The product-based custom fields thing 
should be a UI-only setting. But that's orthogonal to the question of 
whether they should be in the bugs table or not.

Adding them to the bugs table will produce a lot of null values for the 
inapplicable fields; the bugs table would not be normalised correctly. I 
believe that's frowned upon in database design (although perhaps someone 
more knowledgeable will correct me there.)

Gerv