A follow on question I have is if the relationship is specified
this way can you prevent the deletion of the activity
records when the account record is deleted?
On Sat, 2006-09-02 at 11:25 -0400, Michael Bayer wrote:
> since your AccountActivity does have an actual relationship to the Account
> table, then yes, to go totally ORM would imply that youd have a relation
> on the Account mapping.
>
> mapper(Account, accounts, properties={
> 'activity':relation(AccountActivity, lazy=True)
> }
> )
> mapper(AccountActivity, accountactivity)
>
> when you create a relation as above, it gets a default "cascade" rule of
> "save-update", which indicates that the "save" operation on the parent
> Account object will result automatically in a "save" operation on the
> child AccountActivity object.
>
> if you have potentially many AccountActivity objects for a particular
> Account, and you would like to be able to append AccountActivity instances
> without forcing a load of all the other objects, you can specify
> "lazy=None" on the relationship, which means the relationship will never
> automatically load its contents.
>
>
> James Tauber wrote:
> >
> > I have a table for user accounts[1] and another one[2] for logging
> > all account activity (signup, activation, login, logout, etc)
> >
> > Not surprisingly, the account activity table has a foreign key of
> > account id relating it to the account table.
> >
> > I have an Account class defined:
> >
> > class Account(object):
> >
> > def __init__(self, email_address, full_name, password):
> > self.email_address = email_address
> > self.full_name = full_name
> > self.password_sha = sha.sha(password).hexdigest()
> >
> > which is mapped to the table with:
> >
> > accounts_mapper = mapper(Account, accounts)
> >
> > So I can create new accounts easily with:
> >
> > new_account = Account("[EMAIL PROTECTED]", "James Tauber",
> > "mypassword")
> > session.save(new_account)
> > session.flush()
> >
> > However, I'm wondering the best way to log the account creation (i.e.
> > signup). I can do it after the fact with something like:
> >
> > activity = AccountActivity()
> > activity.account_id = new_account.account_id
> > activity.time_stamp = time.time()
> > activity.activity_type = "SIGNUP"
> > session.save(activity)
> > session.flush()
> >
> >
> > but I'm just wondering if there's a good way I can do it as part of
> > the Account creation itself.
> >
> > I have done this sort of thing previously in PostgreSQL with triggers
> > but I'd like a more DB-neutral approach (that will also work with
> > sqlite) using SQLAlchemy.
> >
> > Any tips?
> >
> > Would a better approach be to add a property:
> >
> > accounts_mapper.add_property("activity", relation(AccountActivity))
> >
> > and then just do a self.activity.append(AccountActivity(...))?
> >
> >
> >
> > James
> >
> >
> > [1]
> >
> > accounts = Table("accounts", meta,
> > Column("account_id", Integer, primary_key = True),
> > Column("email_address", String(255), unique = True, nullable =
> > False),
> > Column("full_name", String(255)),
> > Column("password_sha", String(40), nullable = False),
> > Column("status", String(6), default = "NEW", nullable = False),
> > # NEW, ACTIVE, LOCKED
> > )
> >
> >
> > [2]
> >
> > account_activity = Table("account_activity", meta,
> > Column("account_activity_id", Integer, primary_key = True),
> > Column("account_id", Integer, ForeignKey("accounts.account_id"),
> > nullable = False),
> > Column("time_stamp", DateTime, nullable = False),
> > Column("activity_type", String(8), nullable = False), # SIGNUP,
> > ACTIVATE, RESET, LOGIN, LOGOUT
> > )
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