> David

> It is very difficult to make a TDataset descendant that work on Ms ADO or
> DAO as they do not allow to lock a record and then move, as TDataset need.

> Example :

> If you edit a record in a grid, recordset should be in edit mode.
> Then you resize the grid : the grid so the TDataset ask for data, so you
are
> obliged to move through your recordset.
> At this time you recordset is no longer in Edit mode...

> Perhaps Mark and others Borland developpers have a solution.

> Alex

> David Chaumont <da...@chaumontsystems.com> a crit dans le message :
> 7vafl3$cg...@forums.borland.com...
> > Did anybody get the record locking to work in ADO with access 97/2000
> using
> > JET 4.0 ? I have an application residing on a server with the .mdb file
> and
> > if we both edit a field of a particular row it will let both of us do
it..
> > I've been wasting hours on this and tryed many settings and nothing
seems
> to
> > work.. Help.

> > David

> > Ok thanks.. Guess i'll wait for more feedback. Anybody else have any
info on
> > this subject for me?

> The ADOExpress components don't directly support pessimistic record
locking
> because ADO itself does not have any way to arbitrarily lock a given
record and
> still support navigating to other records.

> There is something that you can try, but keep in mind it won't work if you
do
> something that forces a reread of data from the underlying recordset.  In
the
> AfterEdit event of your dataset add the following code:

>   ADODataSet1.UpdateCursorPos;
>   ADODataSet1.Recordset.Fields[0].Value :=

> You must have CursorLocation set to clUseServer.

> One other option might be to use a cloned cursor to manage the locking.

> Good luck,

> Mark

> I really agree with your explaination : This is a ADO/DAO behaviour :
> It is not possible to lock a spcific record, only the current one...

> After spending our to find a solution to correct the same problem with
DAO,
> I think that there is not solution.
> If I remember in DAO Recordset.Clone can have different position, order
but
> not state. Perhaps it is possible in ADO.

> Today I use a table to store locks manually (in fact a TDataset descendant
> that automatically do the job).
> This is the best solution :
> - You can lock a single record (and not a page)
> - You can lock several records
> - You can retrieve the lock owner information (name, machine, etc...)

> Alex

> Mark Edington (Borland) <meding...@nolunchmeat.com> a crit dans le
message
> : 7vqavh$j...@forums.borland.com...
> > David Chaumont <da...@chaumontsystems.com> wrote in message
> > news:7vccjn$sn018@forums.borland.com...

> > > Ok thanks.. Guess i'll wait for more feedback. Anybody else have any
> info on
> > > this subject for me?

> > The ADOExpress components don't directly support pessimistic record
> locking
> > because ADO itself does not have any way to arbitrarily lock a given
> record and
> > still support navigating to other records.

> > There is something that you can try, but keep in mind it won't work if
you
> do
> > something that forces a reread of data from the underlying recordset.
In
> the
> > AfterEdit event of your dataset add the following code:

> >   ADODataSet1.UpdateCursorPos;
> >   ADODataSet1.Recordset.Fields[0].Value :=
> ADODataSet1.Recordset.Fields[0].Value;

> > You must have CursorLocation set to clUseServer.

> > One other option might be to use a cloned cursor to manage the locking.

> > Good luck,

> > Mark