I would prefer to leave this as it is for backward compatibility
reasons but you can do Field(...., ondelete="no action") correct?
In any case open an issue on google code.
On Aug 17, 2:16 pm, Omi Chiba <ochib...@gmail.com> wrote:
> I was fololwing the web2py book with mssql for my database.
>
> db.define_table('comment',
> Field('page_id', db.page),
> Field('body', 'text'),
> Field('created_on', 'datetime', default=request.now),
> Field('created_by', db.auth_user, default=auth.user_id))
>
> will generate
>
> CREATE TABLE comment(
> id INT IDENTITY PRIMARY KEY,
> page_id INT NULL, CONSTRAINT comment_page_id__constraint FOREIGN
> KEY (page_id) REFERENCES page(id) ON DELETE CASCADE,
> body TEXT NULL,
> created_on DATETIME NULL,
> created_by INT NULL, CONSTRAINT comment_created_by__constraint
> FOREIGN KEY (created_by) REFERENCES auth_user(id) ON DELETE CASCADE
> )
>
> and will cause the error says:
>
> Introducing FOREIGN KEY constraint 'comment_created_by__constraint' on
> table 'comment' may cause cycles or multiple cascade paths. Specify ON
> DELETE NO ACTION or ON UPDATE NO ACTION, or modify other FOREIGN KEY
> constraints.
> Msg 1750, Level 16, State 0, Line 1
> Could not create constraint. See previous errors.
>
> The details for the error is descrived in
> herehttp://support.microsoft.com/kb/321843
>
> After I made the change on dal.py it worked fine.
>
> def __init__(
> self,
> fieldname,
> type='string',
> length=None,
> default=DEFAULT,
> required=False,
> requires=DEFAULT,
> # ondelete='CASCADE',
> ondelete='NO ACTION',
>
> Can we make this change as path to avoid the error for mssql ? I'm not
> sure if other database has the same problem.
