Re: Persistence

frebe73@xxxxxxxxx a écrit :

While relational models focus on flexibility in how they represent
information, object models don't benefit from this flexibility. There
is no single object model that can express enough semantic precision
for all applications.

Indeed.

Object models aren't supposed to capture all the
relationships among the information components, only those that are
relevant to the business context of a particular application.

I don't know if "supposed" is the correct word. I think "isn't able to"
is more correct.

Are you here only for bashing, or are seriously interested in OO ?

If an object model has several disadvantages compared
to a relational schema, why use it at all?

Do we have to see the fact that a given application doesn't need to use
all and every possible relationships from a given relational model as a
"disadvantage" ? Most SQL DBMS client applications are meant to somehow
"specialize" (IOW: restrict) the user's view of the informations. In
this context, we don't even care about "ability" to capture all and
every possible relationships.

How do we know an object
model is flexibale enough for the particular business context?

This is another question.

(snip)
If you don't need anything but persistence, persisting objects directly
would make sense. But mostly you really need the other features
provided by a RDBMS.

I don't get you here... Do you mean that every OO program absolutely
needs a SQL DBMS ?

.