Re: [SQLObject] Foreign Key + Constraints?

[Sidnei da S. <si...@aw...>]

On Wed, Dec 03, 2003 at 10:28:08AM -0600, Ian Bicking wrote:
| On Dec 3, 2003, at 8:59 AM, Sidnei da Silva wrote:
| >I just realized that when using ForeignKey, the created table doesn't
| >create the foreign key constraints. I would like to add that + the
| >'cascade' option to ForeignKey, at least on Postgres. Is there any
| >objection on doing so?
| 
| That's fine.  It would be nice if MySQL and SQLite could also do 
| cascades, from the SQL side, i.e., destroySelf() would do the cascade 
| manually -- at least consider the necessary hooks.  Firebird is 
| probably like Postgres, but I don't know if the syntax matches.

Ok, attached is my first try. There's two things I would like to
discuss before going on supporting the other databases:

First, I'm getting the 'foreign' class via findClass(col.foreignKey),
without passing the registry parameter, because AFAICT, I can't get to
the SQLObject class from the column. Is that correct? How much trouble
can that buy us? :)

Second, I think that as I'm getting the 'dependent'[1] classes via
findDependencies, It would be simple to pass them into
DBConnection.dropTable() so that we can do the cascade the manual way
-- by iterating on the result of select() and calling destroySelf() on
each object. Does that sound reasonable?

[1] I considered 'dependent' a class that has a column which refers to
our class on the 'foreignKey' attribute, and also has 'cascade' set to
True.

Thoughts?

-- 
Sidnei da Silva <si...@aw...>
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