[Zope-dev] Bulletproof ZCatalog proposal

[Phillip J. Eby]

At 09:34 AM 6/7/01 -0400, Shane Hathaway wrote:
>
>One thing I didn't make clear in the proposal is that I'm interested in 
>repurposing ZCatalog as a general ZODB indexing mechanism and 
>essentially moving it down from the application layer to the database 
>layer.  Catalogs would be updated automatically (in a lazy fashion to 
>avoid performance penalties).  There would potentially be a large 
>number of catalogs, though, so the number of conflicts would increase 
>significantly.
>
>But I think I have a solution for all of the issues in conflict 
>resolution.  If you, or anyone else, is also interested in this, please 
>show support (if only by saying "please do this"!) :-)  I can't work on 
>it unless I have a reason to.
>

Sounds cool.  At one time Ty and I thought we might do something like this
by adding to a linked list of "pending updates" which the catalog would use
to alter its search results, until the list got "too long", at which point
it would post the actual updates.  The only catch was that this would still
produce conflicts at the head end of the linked list.  :(  Of course, that
was in the days before ZODB conflict resolution.  Nowadays, you could
probably implement it as a simple sequence object with the conflict
resolution method implemented.  But then there'd be the question of how to
resolve conflicts if more than one thread or ZEO client decided to apply
the queued changes...  a 100 conflicts vs 1 situation.  Ugh.

Anyway, I'd be really interested in seeing "a solution for all the issues
in conflict resolution".  Will it help with arguments, too?  How about
world peace?  ;)