* [EMAIL PROTECTED] <[EMAIL PROTECTED]> [070127 14:32]: Yeah, but the problem is that you need to think of that beforehand. Or you have to change the widget class, potentially all places that use the widget class, and go over all your widgets in the database to add this backlink.
While with relational databases, you are way quicker when the users come up with some crazy requests for data. > If you need concurrent access in in OO database just write your code to > handle it. For some applications you could just add and xml-rpc server to > your code. For simple applications this can be accomplish with just a couple > lines of code. I realize that concurrent access is built into a relational > database but it does come at a cost. Applications that don't need it will > run slower than necessary as they have to open and close connections, build > query strings just to have the database parse it and the data being passed > around have to be converted to and from strings if they aren't already > strings. For many applications this overhead is not significant but in > others it is. For an application that needs only 1 query every few minutes > it won't be a problem but if you have one that needs 10,000 queries per > second it will be a show stopper. > > > Basically, ORM try to make a nice interface for an ugly world. Good. > > OODB are nativly nice. Trouble is that the world most often is not a > > nice place to be. And with a hierarchical database, querying data in > > any unexpected way breaks down badly. > > > > Like I said if you need ad-hoc queries than a OO database is wrong for you > application. Now if every now and then you need to access data in your OO > database in a way that you didn't think of the just modify the code for your > OO database. This is no different than having to change your scheme in a > relational database. You are not likely going to get either one of them it > right or complete from the beginning. Ok, I'm completly with you on this: OO db are fine for a part of the problem space where you can be sure that you will never need to run some quick'n'dirty reports for the boss of your boss. Problem here, it's hard to be sure if you will need these reports before you are in production. Your business department will swear that they won't ask you the click through rate for some ads. And then, 2 weeks after you started production for money, they'll sneak in, and ask you "to give them clicks and impressions. Would be nice if you could calculate CTR, but if that's impossible, we'll add the calculation in Excel". So basically, the number of systems where you know that you can forego reporting is small. Andreas --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "TurboGears" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/turbogears?hl=en -~----------~----~----~----~------~----~------~--~---
