Re: DataRelation

From: EijiTek (eijitek_at_comcast.net)
Date: 06/27/04 

Date: Sat, 26 Jun 2004 22:44:16 -0500

Well, I think it really depends on the intent of their application. Keep in
mind that much of the purpose of ADO.NET is to provide a mechanism that
allows for disconnected data access. When working with a connected
environment I've found that it's much better and easier to just query the
data as I need it rather than deal with all of the intricacies of ADO.NET
but a disconnected environment is a totally different beast.

In Web applications I find very little use for the DataRelation class but in
working in environments where I don't have an accessible database or just
need to maintain some data without having a database at all then the
DataRelation class is extremely useful.

"John Wood" <spam@isannoying.com> wrote in message
news:%23dD4JS$WEHA.1888@TK2MSFTNGP11.phx.gbl...
> Oh... well datarelations aren't really that useful if you want your
database
> to be scalable, are they.... You'd think they'd somehow link it up to the
> sqlcommandbuilder, given that it has the columns it needs to request the
> data.
>
> Thanks.
>
> --
> John Wood
> EMail: first name, dot, second name at priorganize.com
>
>
> "EijiTek" <eijitek@comcast.net> wrote in message
> news:yv2dneKYwKdhskPdRVn-uw@comcast.com...
> > The data relation object only creates a relationship between the
in-memory
> > tables. In your example, if the customer table has been populated but
the
> > orders table is empty, calling the GetChildRows() method of any given
> > DataRow will return an empty array. No data will be automatically
> > downloaded since the data table has no knowledge of the origin of the
data
> > (ie: did the data come from a database via a DataAdapter or was it
> manually
> > added?).
> >
> > "John Wood" <spam@isannoying.com> wrote in message
> > news:OqAfMz%23WEHA.2792@TK2MSFTNGP10.phx.gbl...
> > > When you set up a DataRelation, does the data need to already be
present
> > in
> > > the table, or will it query dynamically to fill up the data to fulfill
> the
> > > relationship?
> > >
> > > eg.
> > > Customer is the parent table, orders it the child table. Orders is
> empty.
> > > I navigate from Custom to Order using a DataRelation, will it
> > automatically
> > > send out the SQL to request the related orders?
> > >
> > > --
> > > John Wood
> > > EMail: first name, dot, second name at priorganize.com
> > >
> > >
> > >
> >
> >
>
>

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