Hi George, George Sakkis wrote:
> Google for "many-to-many relationships". In short, you have two entity > classes (say emails and labels) where each instance of one entity may > be associated to zero or more instances of the other entity. In > databases you implement this by having three tables, one for each > entity and one for their association: > > Email RelEmailLabel Label > ---------- -------------- --------- > ID <--- EmailID ID > subject LabelID ---> name > ... ... > Ok, but how can I keep my Relationship Table out of bugs, bad data?! I wonder how i'll control the following: 1st) Given an generic email, in which group(s) is it contained? 2nd) Given a group, which Emails/contacts does it contain? I don't have much expererience with databases (yet). Will the pysqlite work with ease? Because I don't mean to make a big big program, just something very simple for my personal use. > > Then you can associate mails to labels by joining all three tables > together on the IDs. Of course you can implement this in memory as well > but you should probably want to store them in some persistent area > anyway, so an rdbms the way to go. Sqlite (with pysqlite) would meet > your needs just fine. I'll google for this module tomorrow and try to learn something about it. I plan to post the code I manage to write. BTW which is the best way to store all those data files? Plain text files? Some kind of binary file? or what? Thank you once again, Rodolfo -- http://mail.python.org/mailman/listinfo/python-list
