Re: abstract class with Class::DBI

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On Wed, Oct 20, 2004 at 05:40:26PM +0100, Tom Hukins wrote:
> The schema and code you use sets has_a relationships on primary keys.
> See the note at the end of the has_a section in Class::DBI's
> documentation that suggests you avoid this.

Tom, I presume you are talking about this note:

  *NOTE* You should not attempt to make your primary key column inflate
  using has_a() as bad things will happen. If you have two tables which
  share a primary key, consider using might_have() instead.

I was hoping that one of the developers would say something about your
statement. I don't think that setting a has_a relationship on a primary
key is the same as inflating it. I use this setup all the time and have
not seen problems.

At the beginning of the section on has_a, the POD states:
  We generally use 'has_a' to supply lookup information for a foreign key,
  i.e. we declare that the value we have stored in the column is the
  primary key of another table.


> I'm working with a similar schema at the moment, and can attest to
> "bad things happening" as the documentation claims.

Were you inflating the primary key or setting up a relationship? What
bad things were happening?


> I also considered storing identical IDs in two columns, one for the
> primary key and one for the has_a relationship, but this felt like too
> much of a messy hack.

Messy and unnecessary.


William

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