[Zope-dev] Bulletproof ZCatalog proposal

Shane Hathaway shane@digicool.com
Thu, 7 Jun 2001 09:34:54 -0400


On Thursday 07 June 2001 07:43, Toby Dickenson wrote:
> > Large catalog
> >updates (where every object is reindexed) also generate a lot of
> >conflicts.
>
> Is that last bit true? I thought 'Update Catalog' created *new*
> indexes. There might be a conflict on the root catalog object, but
> not on the index BTrees.

I should say large catalog updates tend to generate a conflict.  It 
really doesn't matter how many conflicts there are.  Within a single 
transaction, 1 conflict is as bad as 100.

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.

Shane