subraman@andromeda.rutgers.edu (Ramesh Subramanian) (05/09/91)
I am very new to the field of OO systems, and have the following
questions regarding OODBs. They are probably very naive to most
OO experts. I would appreciate any answer.
1. What exactly are `views' as related to OODBSs ?
In relational DBs, views are relations specified by the user at run time,
or earlier, and whose tuples are made up of attributes from a combination
of existing relations.
How can one create a view in an OODB ? Will it be a new object which has
the properties (attributes) of a combination of objects ?
Is it possible to specify these views during run time ? Is there a need
for specifying views at all, in OODBs?
2. How inherent are `rules' to OO systems ?
Some systems speciifically provide a `rule' object whose instances
are rules. Such systems also have an implicit `rule system' which takes
care of rule processing (resolution, etc.) [e.g. Intellicorp's KEE]
Other systems do not explicitly mention rules. Does it mean that
rules as objects, and rule processing are considered as `given' in
such systems, or is it just that `rules as inherent to OODBs' is
a relatively recent idea ?
Again, would appreciate any idea or pointer that you may have.
Thanks,
Ramesh Subramanian subraman@andromeda.rutgers.edu