On Feb 2, 2007, at 10:33 AM, svilen wrote:
> A mincut algorithm finds the minimal number of edges to cut in a
> cycled graph so it becomes without cycles.
>
> http://en.wikipedia.org/wiki/Max-flow_min-cut_theorem
>
> i.e. applying such algorithm over the graph of table dependencies
> (foregnkey), one gets some minimal number of foreign keys to make
> use_alter=True.
> there might be many solutions.
>
> or in the mapper/relation graph, find which relations to make
> post_update=True so although obj-relaltions are cycling, the
> mapper/relations have no cycles.
>
> is it more clear now?
>

no, not at all.  thats the article I read, and it applies to a "flow  
graph", which as far as I can tell has to apply numerical values to  
each edge in the graph and applies a "capacity" to the nodes.  I dont  
see what "numerical" or "capacity" values would be applied to a  
topological sort.

class User
class Address

User -> one to many -> Address

whats the "capacity" for that graph ?  whats the "x/y" to stick  
between those two nodes ?

also, this whole topic is not very important to me, as its easy  
enough for someone to just add a "post_update" into their mapping  
configuration when an obvious inter-row dependency is detected.





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