Re: [Openinteract-help] OI2 and DB Entity Relationships

[Chris W. <ch...@cw...>]

On Dec 10, 2004, at 6:28 PM, Coder wrote:
> I am having trouble understanding how the OI2 architecture models 
> entity
> relationships in code and susequently referes to the at run time.

There are a couple of things to separate here.

  - OI2 uses SPOPS for its entities. This might change to be more 
flexible, but not in the very near future.
  - OI2 has very good support for SPOPS as an object-relational mapping 
tool
  - OI2 does not preclude other mapping tools

The only reason OI2 does not support Class::DBI is that nobody who has 
known enough about Class::DBI has stepped forward as a guinea pig to 
test out integration. (Which should actually be quite minor.) Will you 
be the first? :-)

Here's what I mean by minor:

  - Class::DBI objects should be able to use OI2 datasources. This means 
you'll only have to define database information in one place. I assume 
this means you wire up a method in Class::DBI to return a database 
handle on demand, but that might just be how I think about things. 
(This is very easy, BTW.)

  - We need to initialize Class::DBI objects at startup. This could be 
as simple as listing a set of class names and having OI2 require() them 
all. (Also very easy.)

  - Is there any data definition language manipulation? That is, so you 
can do something like:

    My::Class::DBI->create_tables( 'mysql', $dbh );

I think that's it. There are likely other possiblities -- looking up a 
CDBI class by name vs hardcoding a class name (like the rest of OI2), 
doing any one-time initialization at package installation.

Is there anything I'm missing?

Chris

--
Chris Winters
Creating enterprise-capable snack systems since 1988