> You can look at the space wasted in percentages.
> Also, every query will have to check the type field.

> IMHO, column aggregation should be considered only if you have many
> different inherited classes with small tables (up to a few thousands
> of rows). In your case, concrete seems more convenient.

> Cheers

> 2008/5/15 Alex:
>     Well, you only get an additional 2 columns, one tinyint and one
> integer, per row. Is that such a waste?

>    For some reason duplicating the same table structure twice seems
> icky, though it might not be.

>     On Wed, May 14, 2008 at 8:40 PM, colnector wrote:

>        Doesn't this create comment_id and item_id in the same votes
> table?
>        How is that better than using 'concrete inheritance' where
> different
>        tables are created?
>        One should always consider what's going on behind the scenes
> in the
>        DBMS. It seems to me that using column aggregation as
> presented here
>        is wasteful of both time and space.

> On May 14, 9:13 pm, Alex <outroa...@gmail.com> wrote:
> > How does this look?

> > Vote:
> >   tableName: votes
> >   actAs:
> >     Timestampable:
> >       created:
> >         name: created_at
> >         type: timestamp
> >         format:Y-m-d H:i:s
> >       updated:
> >         disabled: true
> >   columns:
> >     id:
> >       unsigned: 0
> >       primary: true
> >       notnull: true
> >       autoincrement: true
> >       type: integer
> >     user_id:
> >       unsigned: 0
> >       primary: false
> >       notnull: false
> >       autoincrement: false
> >       type: integer
> >     vote_type_id:
> >       unsigned: 0
> >       primary: false
> >       notnull: false
> >       autoincrement: false
> >       type: integer
> >   relations:
> >     sfGuardUser:
> >       local: user_id
> >       foreign: id
> >       type: one

> > VoteItem:
> >   inheritance:
> >     extends: Vote
> >     type: column_aggregation
> >     keyField: type
> >     keyValue: 1
> >   columns:
> >     item_id:
> >       type: integer

> > VoteComment:
> >   inheritance:
> >     extends: Vote
> >     type: column_aggregation
> >     keyField: type
> >     keyValue: 2
> >   columns:
> >     comment_id:
> >       type: integer

> > Advantage is that it maintains FK restrictions.

> > On Wed, May 14, 2008 at 2:07 PM, Jonathan Wage <jonw...@gmail.com>
> wrote:
> > > Just having a model with record_type and record_type_id, and you would
> set
> > > the fields yourself?

> > > - Jon

> > > On Wed, May 14, 2008 at 12:02 PM, Alex <outroa...@gmail.com> wrote:

> > >> What would be an alternate solution?

> > >> - alex (from iphone)

> > >> On 14-May-08, at 1:43 PM, "Jonathan Wage" <jonw...@gmail.com> wrote:

> > >> I think that column aggregation is the best solution right now.

> > >> - Jon

> > >> On Wed, May 14, 2008 at 11:20 AM, Alex < <outroa...@gmail.com>
> > >> outroa...@gmail.com> wrote:

> > >>> But with column aggregation I also have to define an additional
> column
> > >>> manually. It generates a TYPE column, but then I also need to create
> a
> > >>> TYPE_ID column so that the vote corresponds to the right item or
> topic.

> > >>> What's the ideal solution?

> > >>> - alex (from iphone)

> > >>> On 14-May-08, at 11:51 AM, "Jonathan Wage" < <jonw...@gmail.com>
> > >>> jonw...@gmail.com> wrote:

> > >>> Simple inheritance is one table with all columns on the parent.

> > >>> You want something like column aggregation inheritance it sounds
> like.

> > >>> - Jon

> > >>> On Tue, May 13, 2008 at 5:17 PM, Alex < <outroa...@gmail.com><
> outroa...@gmail.com>
> > >>> outroa...@gmail.com> wrote:

> > >>>> What exactly is simple inheritance? With what I have below, it
> doesn't
> > >>>> create any addiotional tables. How will I be able to query only
> votes
> > >>>> for Items?

> > >>>> Thanks!

> > >>>> Vote:
> > >>>>  tableName: votes
> > >>>>  actAs:
> > >>>>    Timestampable:
> > >>>>      created:
> > >>>>        name: created_at
> > >>>>        type: timestamp
> > >>>>        format:Y-m-d H:i:s
> > >>>>      updated:
> > >>>>        disabled: true
> > >>>>  columns:
> > >>>>    id:
> > >>>>      unsigned: 0
> > >>>>      primary: true
> > >>>>      notnull: true
> > >>>>      autoincrement: true
> > >>>>      type: integer
> > >>>>    user_id:
> > >>>>      unsigned: 0
> > >>>>      primary: false
> > >>>>      notnull: false
> > >>>>      autoincrement: false
> > >>>>      type: integer

> > >>>> VoteItem:
> > >>>>  inheritance:
> > >>>>    extends: Vote
> > >>>>    type: simple

> > >>>> VoteComment:
> > >>>>  inheritance:
> > >>>>    extends: Vote
> > >>>>    type: simple

> > >>> --
> > >>> Jonathan Wage
> > >>> <http://www.jwage.com> <http://www.jwage.com>http://www.jwage.com
> > >>>  <http://www.centresource.com> <http://www.centresource.com>
> > >>>http://www.centresource.com

> > >> --
> > >> Jonathan Wage
> > >> <http://www.jwage.com>http://www.jwage.com
> > >> <http://www.centresource.com>http://www.centresource.com

> > > --
> > > Jonathan Wage
> > >http://www.jwage.com
> > >http://www.centresource.com

> > --

> > - Alex