This one time, at band camp, Robin Munn wrote: >Have you looked at >http://www.sqlalchemy.org/docs/adv_datamapping.myt#advdatamapping_joins >yet? From those docs, it looks like you should be able to simply do >"mapper(Person, join(account, person))" and have it work as you >expect, with a two-column primary key on the Person objects composed >of the primary keys of each table (account and person). In other >words, do exactly what you were trying to do, but without the >"properties = ..." part.
Yup, actually I found that right after posting. Here's a bit more example code, with almost the same tables (few extra fields) mapped with exactly the above mapper: p = Person(handle='testguy', firstname='Testguy', lastname='McTest', phone='+62195555555', email_address='[EMAIL PROTECTED]', password='test') session.save(p) session.flush() pid = p.id session.clear() del p p = session.get(Person, pid) assert p is not None This generates the following dump from the engine: [2006-05-29 19:29:16,706] [engine]: BEGIN [2006-05-29 19:29:16,708] [engine]: INSERT INTO account (email_address, password) VALUES (?, ?) [2006-05-29 19:29:16,708] [engine]: ['[EMAIL PROTECTED]', 'test'] [2006-05-29 19:29:16,709] [engine]: SELECT account.id, account.email_address, account.password_hash, account.activated FROM account WHERE account.id = ? [2006-05-29 19:29:16,709] [engine]: [1] [2006-05-29 19:29:16,711] [engine]: INSERT INTO person (id, account_id, handle, firstname, lastname, phone, fax) VALUES (?, ?, ?, ?, ?, ?, ?) [2006-05-29 19:29:16,711] [engine]: [1, None, 'testguy', 'Testguy', 'McTest', '+61295555555', None] [2006-05-29 19:29:16,712] [engine]: COMMIT [2006-05-29 19:29:16,800] [engine]: SELECT person.fax AS person_fax, person.handle AS person_handle, person.account_id AS person_account_id, person.firstname AS person_firstname, person.lastname AS person_lastname, account.activated AS account_activated, person.phone AS person_phone, account.email_address AS account_email_address, person.id AS person_id, account.id AS account_id, account.password_hash AS account_password_hash FROM account JOIN person ON account.id = person.account_id WHERE account.id = ? AND person.id = ? ORDER BY account.oid [2006-05-29 19:29:16,800] [engine]: [1, 1] First thing to note is that the order in which the rows are entered depends entirely on the join order, i.e. person will be inserted first if the mapper looks like mapper(Person, join(person, account)). Second thing to note is that the account_id inserted into person is None, not the result of the previous select that supposedly retrieves it. Finally, the select that is retrieving the object at session.get has an extra unnecessary WHERE clause; that of account.id = ?. As we are already joining on account.id = person.account_id, this is redundant and may cause invalid results, should person.account_id actually contain valid data. Mike, is that enough to create a unit test? >I haven't actually tried this yet, so if you've already read those >docs and it's not working, then I don't know how to help you. But it >sure sounds from the documentation like what you're trying to do ought >to work. Yeah ;-) ------------------------------------------------------- All the advantages of Linux Managed Hosting--Without the Cost and Risk! Fully trained technicians. The highest number of Red Hat certifications in the hosting industry. Fanatical Support. Click to learn more http://sel.as-us.falkag.net/sel?cmd=lnk&kid=107521&bid=248729&dat=121642 _______________________________________________ Sqlalchemy-users mailing list Sqlalchemy-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/sqlalchemy-users
