There is a Slashdot article and discussion about OO database vs.
relational databases. They mentioned OID right at the beginning.
They guy mentions six advantages of OO databases and only one
disadvantage, but it is an interesting read to see how the PostgreSQL
features match some of the OO features.
The main argument is that mapping relational tuples into object-oriented
classed in your application is a pain:
http://slashdot.org/article.pl?sid=01/05/03/1434242&mode=nested
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