[Zope-dev] Re: ZOBD and pointers

2005-06-21 Thread Tim Peters
[Yair Benita] Reading this answer I understand that anything I store should be persistent, even if its a list I don't plan to edit. [Tim Peters] I wouldn't say that. For example, for _most_ applications it would be foolish to create a subclass of Persistent to store an integer, as opposed

[Zope-dev] Re: ZOBD and pointers

2005-06-21 Thread Tres Seaver
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Tim Peters wrote: [Tres Seaver] Making the attribute a persistent sub-object also eliminates the chance of a ConflictError based on changes to the other attributes. I didn't follow that one. If other attributes change, they can trigger

[Zope-dev] Re: ZOBD and pointers

2005-06-20 Thread Laurence Rowe
As far as I am aware, ZODB will store a list of pointers to the lists of z objects. What you should be careful of for efficient use of ZODB is that your list is stored in an efficient way, well if the list is updated often or long anyway. When you pack your ZODB does it take up a lot less

Re: [Zope-dev] Re: ZOBD and pointers

2005-06-20 Thread Tim Peters
[Laurence Rowe] ... Unless you use a special PersistentList ZODB will have no choice but to store a new copy of the whole list when that list is modified. Caution: that's true of a PersistentList too. The purpose of PersistentList isn't realy to supply more-effecient storage (that's the

[Zope-dev] Re: ZOBD and pointers

2005-06-20 Thread Tres Seaver
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Tim Peters wrote: [Yair Benita] ... Reading this answer I understand that anything I store should be persistent, even if its a list I don't plan to edit. I wouldn't say that. For example, for _most_ applications it would be foolish to create