Re: Trivial Question

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> -----Original Message-----
> From: Michael G Schwern [mailto:schwern@xxxxx.xxx]=20
> Sent: Sunday, June 12, 2005 2:16 AM
> To: cdbi-talk@xxxxxx.xxxxx.xxx
> Subject: Re: Trivial Question
>=20
>=20
> On Sat, Jun 11, 2005 at 10:49:31PM +0100, Tony Bowden wrote:
> > On Sat, Jun 11, 2005 at 01:32:16PM -0700, Michael G Schwern wrote:
> > > I would presume the result of $obj->gimme_hash would be=20
> equivalent to:
> > > 	my %hash;
> > > 	foreach my $col ($obj->columns) {
> > > 		$hash{$col} =3D $obj->$col();
> > > 	}
> > > No?
> >=20
> > Well, in the general case there's all sorts of issues here=20
> with inflated
> > columns, triggers, even overriden methods.
>=20
> Shouldn't this all be taken care of due to the fact that its=20
> going through
> each column's accessor?

Not always, since the column accessor can give you an object reference
anyway.
For example, think of a CDBI class that has a /has a/ relationship with
another class (ForeignClass) on a given column.

In this case

	$obj->$col();

would give you something like

	ForeignClass=3DHASH(0x21404bc) # there is a little inexactitude
	                             # in the docs about this...

while in the corresponding DB field you have a value of the primary key
of the "foreign table".
However in string context a CDBI object reference returns the value of
the primary key (or anything returned by the stringify_self() method, if
provided), that's why it's necessary to force stringification if you
wanna export the column values in a hash, as Cees did (well, you've got
a number of other methods to get this, but they are probably more
complicated).

(Anyway what the column /values/ really are in CDBI is quite a shaded
concept, as Tony pointed out...)

> I guess it depends on what you want:=20
>  What's in
> the database or what the object presents to you.
> I'd lean towards the
> latter simply because its really easy to get the former by=20
> bypassing CDBI.

You are right: if you want exactly the db values in a hash the best
thing to do is probably to resort to raw DBI...

Ciao,
Emanuele.