[EMAIL PROTECTED] wrote: > On Jan 28, 2006, at 2:52 PM, Michael Bayer wrote:
> however, if i'm following what you're doing > correctly then this doesn't matter anymore? it > sounds like you're doing general cycle detection > at the table/class level, and dropping back to > row/instance topo-sorting if you detect a cycle? yes ! in fact i think this code also is needed anyway since I have a feeling the current "cyclical" code is not 100% functional, possibly in the case of deletes of non-cylical child items. > (an aside - do the tasks get partitioned based > on connected-components? i.e., if there was one > cyclic task and a bunch of non-cyclic ones, is > the "extra work" isolated to just the cyclic > task? ... well its actually not much "extra work", its just the order that it performs it. the non-cyclical dependencies dont get broken up, they get placed in the usual place they would be amongst the cyclical dependencies. I have flip flopped a little bit on this but i think thats how it will be. > i still don't entirely get how the > task hierarchy is constructed). me neither ! it grew a little organically so ive been trying to refactor and clarify as much as possible in the new branch. > > in any case, to answer your question, within > my actual single self-ref table, i may > occasionally need to create row-cycles. (such > a cycle is "wrong" based on the semantics of > our table, but sometimes we have to store > incorrect data for later analysis ... ) well crap ! if you want to map objects to that, I dont really know how to do that automatically...since at some point, you have to INSERT + UPDATE for a single row to break the cycle....implying some hand-queries stuck into the commit phase. except I dont quite know how a developer could do that unless he or she bypasses the entire topological sort completely (since it will otherwise raise an exception....) > > finally, i seem to have mostly worked out what > i need to integrate sqlalchemy into my main > application, ah well, terrific ! - mike ------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Do you grep through log files for problems? Stop! Download the new AJAX search engine that makes searching your log files as easy as surfing the web. DOWNLOAD SPLUNK! http://sel.as-us.falkag.net/sel?cmd=lnk&kid=103432&bid=230486&dat=121642 _______________________________________________ Sqlalchemy-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/sqlalchemy-users
