RE: [PEAR-DEV] OO -> RDBMS mapping

At 11:08 AM 11/1/2002 +0100, Lukas Smith wrote:

Hmm I'm not quite sure.JDO includes mapping of class hierarchies to

RDBMS,

not sure how that would work - can you give an example? (or url) .. dataobjects forces you to make a class for each table, - so making

one

class extend another table... should be possible.

There are a few ways of doing this mapping. If you want performance than you can map the whole hierarchy to the same table. If you want to save space you can map each class to a separate table and use a join. There are also some other ways. but it also means messing with existing tables whenever you add a new class to the hirarchy. Adding another table is cleaner there ...

As I said it's a matter of trade-offs. My idea was seeing if there's any interest for creating a JDO a-like API in PHP not to talk about the specific implementation options right now :)

And if you want performance you would use an OO-DB (never messed with one of those though)?

Not many companies are willing to put their data in OO-DB's as they are relatively young. You can reach very good performance with OO->RDMBS btw. Andi