[vtk-developers] Re: vtkSQLDatabase

[Sebastien BARRE]

At 11/28/2007 03:12 PM, David C Thompson wrote:

>I think that falls under syntactic sugar. It would save having to call
>Delete() and then CreateFromURL() when changing databases, but not
>provide any change in performance (or perhaps a small decrease as each
>call on the database would have to be forwarded to a concrete instance
>if I understand your proposal correctly -- but I don't think it would be
>a significant impact).
>
>In any event, you've sold me on SetURL being protected. Unless Sebastien
>is morally opposed to CreateFromURL (it didn't sound like it to me),

I'm not, I was just passing by, curious about this new DB framework. 
And I'm French, we don't have morales :)

More seriously, there was also a performance issue in the back of my 
head, but I'm not sure if it is relevant right now: what about 
caching? Database caching can be a serious concern and lead to 
significant improvements. While there are *already* DB caching tools 
available that can be plugged at different levels, is it far fetched 
to think that we could need one that uses information only available 
at the VTK/pipeline level? If that's the case, wouldn't recreating an 
object invalidate such a cache, if it was to be implemented at the 
database class level? Of course I guess we could have a separate 
cache class, etc etc. Just my 2 cents here.