I want to define tables as follows: 1) extend t2_person with additional fields some of which are references to other tables (many people work in "department" x?) 2) all tables to have created_by and modified_by fields (which themselves refer to t2_person)
The problem is that to satisfy 1) I must define "department" before t2_person. To satisfy 2) I must define t2_person before "department". If I import T2 before "department" to get a reference to t2_person, the re-definition of t2_person throws "table already defined". Is the only solution to define my own "person" table that contains the reference to "department" and a reference to t2_person? ...and then import T2 (and t2_person), define "define" then define my "person". If the answer is yes then is that seen as "better design" or a "work- around"? A second problem relates to the desire to navigate efficiently through a database in more than one direction. In the above example, let "person" be a bank account holder and the "other table" be a bank account. Keeping it simple, assume it is a one-to-many relationship, one-or-more accounts each owned by 1 account holder. If the only reference is from person/account holder to account then a search to see who owns account 12345678 is costly. If the only reference is from account to person/account holder then the search for "accounts for this account holder" is costly. However, in web2py, I cannot define an account with a reference to person/account holder and a person/account holder with a reference to account as one of the other definition fails with an undefined term. I believe I have to define a third table: person, account and account_holder to overcome this. Is that correct? It seems the bottom-line is that the database design is constrained by the fact that the table definitions are validated by python in a single pass. If that is true it seems unfortunate. I would be very happy if someone can show me the error of my ways: either the way to define the above tables or explain why I shouldn't want to. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "web2py Web Framework" group. To post to this group, send email to web2py@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/web2py?hl=en -~----------~----~----~----~------~----~------~--~---
