Re: Long Post - Re: How are OO databases doing

Arturo,

The GemStone Facets OODB doesn't directly support SQL queries.

On the other hand, the product's vm supports any Java that one would care to program, including JDBC. You would mount the JDBC driver just as you would in any other Java application. The JTA and JCA standards are also supported, meaning that you could run XA transactions against JDBC and Facets connections. So, in a nutshell, if the relational back end provides a JDBC driver, then Facets can talk to it.

One approach that a number of our customers take is to use the Facets repository in what we sometimes call a Persistent Cache Architecture (PCA). In this architecture the object database is used to persist objects that have been mapped from a relational store. The PCA repository is used for frequently accessed object state (representing recent weeks, months, or even years) where the relational database is used for data warehousing. This can provide a mechanism where the "working set" objects can be accessed by apps that benefit from object transparancy.

There are several techniques that can be used for aging out least recently accessed objects and for maintaining synchronization with the relational back end.

Other customers have no need for the RDBMS, they use Facets as the database of record.

Best Regards,
Bob Walker Received on Tue Feb 21 2006 - 23:12:30 CET