[ZODB-Dev] transacting multiple databases

[Shane Hathaway]

Toby Dickenson wrote:
> On Wednesday 11 December 2002 6:35 pm, Shane Hathaway wrote:
> 
> 
>>... for Zope 3 we should plan to do all "mounting" using cross-database
>>references.  It will be faster and more seamless.  There won't be a
>>"mount point" object that conceals itself; instead, ZODB will just know
>>to load the mounted object from a different database.
> 
> 
> Is seamless a good thing? Right now I like the fact that cross-database links 
> are not handled in the lower layers (DB and down) because it means we can 
> have stronger invariants for those layers, such as reference checking.

That's a good point I had not considered.

> In filesystem terms, today we have a crude equivalent of cross-filesystem 
> symbolic links.   I think there is less usefulness in something like a 
> cross-filesystem hard link (which is what I think you are suggesting), rather 
> than a better symbolic link.

Perhaps in Zope 3 it will be possible to create an object that simply 
emulates all the interfaces of another object, yet gets stored in ZODB. 
  If that worked then it would indeed be a better symlink.

Shane