A pointing to A, is cyclical dependency.
same as A -> B -> A.
but in latter case u must choose one of the links to be added later,
that is use_later=True for ForeignKey.
in former case the table declaration may or may not work without
use_alter.
in both cases u need post_update=True for the relation/mapper of the
loop-closing link of your choice.
On Tuesday 04 September 2007 00:21:06 you wrote:
> Thanks for the reply, what do you mean by cyclic?
>
> On Sep 3, 9:00 pm, [EMAIL PROTECTED] wrote:
> > On Monday 03 September 2007 19:57:54 voltron wrote:
> > > would this work?
> > >
> > > users = Table("users", metadata,
> > > Column("id", Integer, primary_key=True),
> > > Column("username", String(50), unique=True,
> > > nullable=False),
> > > Column("password", String(255)),
> > > Column("email", String(255), unique=True,
> > > nullable=False),
> > > Column("firstname", String(255)),
> > > Column("lastname", String(255)),
> > >
> > > Column("modifiedby_id", Integer, ForeignKey("users.id"))
> > > Column("modifiedon", DateTime(timezone=True),
> > > default=func.now()),
> > >
> > > On Sep 3, 6:50 pm, voltron <[EMAIL PROTECTED]> wrote:
> > > > Excuse the newbie question, how does one declare a
> > > > sef-referencing key? I would like to have fields
> > > > "modified_by" and "created_by" in my users table, the field
> > > > should refer back to the user id or user name in the same
> > > > table.
> > > >
> > > > Thanks
> >
> > yes, foreign key + eventualy use_alter=True if u get cyclic
--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"sqlalchemy" group.
To post to this group, send email to [email protected]
To unsubscribe from this group, send email to [EMAIL PROTECTED]
For more options, visit this group at
http://groups.google.com/group/sqlalchemy?hl=en
-~----------~----~----~----~------~----~------~--~---
