Re: [gnome-db] libgda cursor support

[Murray Cumming <murrayc murrayc com>]

On Thu, 2007-09-27 at 14:39 +0200, Vivien Malerba wrote:
> > > meaning it could not set the iter at the requested row, which is why
> > > it always returns the same value. The reason it returns FALSE is that
> > > it's not implemented (specifically the i_iter_at_row virtual method is
> > > not implemented). Of course it an iterator can move forward and
> > > backward, there could be a default implementation to move it to a
> > > desired row...
> >
> > I guess this should be implemented with FETCH ABSOLUTE.
> > http://www.postgresql.org/docs/8.2/static/sql-fetch.html
> > Does that seem appropriate?
> 
> This could be implemented like that in the GdaPostgresCursorRecordset, yes.
> 
> Otherwise for a more general approach (that is in
> gda_data_model_move_iter_at_row() which is called if no specific
> implementation exists)  we just need to call
> gda_data_model_iter_move_{prev,next} as many times as requested (and
> in the case of the postgres cursor recordset there might even be no
> performance penalty at all because it fetches chunks of rows ar once).

But wouldn't that mean that we have to fetch the data for 1000 rows (100
chunks of 10, for instance) if I just want the data for row 1 and row
1000?

-- 
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