You are using the term runtime. To me that means that I have to go in and
physically change my class-descriptor in the repository.xml. before my app
starts up. Then when the one query has been used I go change the
repository.xml back for all the others and start the app again. I am NOW
assuming that you mean that you can change the class-descriptor
programatically from within the app for a particular query and then restore
it back to it's normal state. Is this accurate? Where is this in the docs
and how do you do it?

I read an email that followed yours and it seemed to be thinking your were
suggesting the same thing :-)

Terminology is a bizarre creature.

Cheers,
Brandon Goodin
Phase Web and Multimedia
P (406) 862-2245
F (406) 862-0354
[EMAIL PROTECTED]
http://www.phase.ws

> -----Original Message-----
> From: Mahler Thomas [mailto:[EMAIL PROTECTED]]
> Sent: Monday, September 02, 2002 9:20 AM
> To: 'OJB Users List'
> Subject: AW: SELECT statements and OJB
>
>
> Hi
>
> >
> > I am thick headed... please forgive me. But one last
> > question. (see question
> > below).
> >
> > > -----Original Message-----
> > > From: Mahler Thomas [mailto:[EMAIL PROTECTED]]
> > > Sent: Monday, September 02, 2002 8:24 AM
> > > To: 'OJB Users List'
> > > Subject: AW: SELECT statements and OJB
> > >
> > >
> > > Hi again,
> > >
> > > > > 1. OJB does *not* perform "select * from", for queries!
> > > > > If you look up objects of class x OJB will read the
> > > > class-descriptor for
> > > > > class x and determine all necessary columns to materialize
> > > > an x instance.
> > > > > The performed select contains all those columns.
> > > > >
> > > > > If you want to limit the number of columns you can modify the
> > > > > class-descriptor for class X do get a reduced number of columns.
> > > > >
> > > >
> > > > So, if i needed a full person to be materialized in one place
> > > > and only the
> > > > id, firstname and lastname elsewhere then I would have to
> > > > write a couple of
> > > > classes and their associated class-descriptor. For example my
> > > > PersonName and
> > > > Person would be two different object classes that are
> > > > populated from the
> > > > same table (PEOPLE).
> > >
> > > NO! You only need one persistent class Person.
> > > You can modify the existing class-descriptor for class
> > Person at runtime.
> > > that is for one query you remove all columns you don not
> > want to see from
> > > the classdescriptor.
> > > After finishing the query you restore the class-descriptor
> > to its original
> > > Form so that all other things work normally.
> >
> > I guess what i am saying here is i need both representations
> > in the same
> > web-app. For example, within the same web application, i have
> > a place where
> > you can 1) select a person to edit and 2) a place to edit a person's
> > information.
> >
> > 1) This requires that i retrieve only the ID, FIRSTNAME AND
> > LASTNAME of all
> > the records in the PEOPLE database. I then display the names
> > on an html
> > page. The user then selects which person they want to edit
> > and we are off to
> > edit that person's info. In this case i only want to populate the id,
> > firstName and lastName variables in the Person object/class
> > and store it
> > into a collection to be traversed on the html page and
> > displayed. My problem
> > arises in reusing my Person class because i already have it
> > in use with step
> > 2's class descriptor. If i undestand you correctly i will
> > have to create a
> > BasicPerson class that only contains the id, firstName and lastName
> > variables and a class descriptor that maps to the BasicPerson
> > class.
>
> As stated in my original mail:
> NO! You only need one persistent class Person!!!
> You can modify the existing class-descriptor for class Person at runtime.
> that is for one query you remove all columns you don not want to see from
> the classdescriptor.
> After finishing the query you restore the class-descriptor to its original
> Form so that all other things work normally.
>
> > Please
> > read on to step 2)
> >
> > 2) This requires that i retrieve all of the fields for a
> > particular person
> > from the database table PEOPLE and populate a Person object
> > to pass to the
> > form that will be populated by that information for editing.
> > Therefore, i
> > would set up my class descriptor to get all the column values from the
> > database and poulate the Person class which has the accordingly mapped
> > setters and getters. At the same time in the same app i have
> > need for just
> > the retrieval of the PEOPLE table's ID,FIRSTNAME and
> > LASTNAME. In this case
> > i am listing all of the names of the people so that a name
> > can be selected
> > to edit a person's info. I don't want to get all the other
> > fields in the
> > records because it would be pointless to populate it with all
> > the colums
> > from the PEOPLE table cuz i don't need them.
> >
> > Conclusion:
> >
> > Now, does this mean that i would have to have two different
> > classes mapped
> > with two different class-descriptors to handle each of these
> > situations.
>
> NO !!!
> (Could somebody else please tro to explain this? I have no idea why you
> still believe that you will need two classes?)
>
> >
> > If yes, then are there any planned enhancements to allow for
> > more efficient
> > reuse of classes?
>
> >
> > I am afraid that you might take my questioning as an insult.
>
> Not as an insult. I simply do not get what you do not understand in my
> reply?
>
> cheers,
> Thomas
>
> > I don't mean it
> > that way. I just want a clear and accurate picture of what i
> > am able to and
> > not able to do. Also, you documentation and work on this is
> > execellent. I
> > know that projects grow faster than their docs and that's
> > just reality.
> > Great Work! I never meant to say otherwise.
> >
> >
> >
> >
> > --
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> > <mailto:[EMAIL PROTECTED]>
> >
>
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