[fpc-devel] About TDataSet master/detail design in fpc

[Uberto Barbini]

> They are not yet implemented. But NestedDataset and DatasetField are
> ONLY for TClientDataset, and we don't support TClientDataset (yet).

Not only, they were first implemented for Oracle object field and they're used 
by some other custom implementation, for example InstantObject exposers use 
them for accessing parts (subobjects).

I began to rewrite something similar for fpc some week ago, I hope to continue 
soon.

> > I'd be glad if someone could explain how the design works and what is
> > expected from a TDataset descendant that support it.
>
> Nothing is expected, i.e. TDataset does not implement anything
> concerning master/detail. How could it ?

Not yet that is.
With NestedDataset in Delphi you could.

> > I'll try to implement it in TSqliteDataSet.

We could collaborate. Maybe you could create a Sqllite broker for 
InstantObject (http://www.instantobjects.org/) too.
Just now the core part of InstantObject (i.e. without presentation) works in 
fpc.

Bye Uberto