Re: For cursors, there is FETCH and MOVE, why no TELL?

Hi

2015-02-09 10:37 GMT+01:00 Marc Balmer <marc(at)msys(dot)ch>:

> Currently there are FETCH and the (non standard) MOVE commands to work
> on cursors.
>
> (I use cursors to display large datasets in a page-wise way, where the
> user can move per-page, or, when displaying a single record, per record.
> When the user goes back from per-record view to page-view, I have to
> restore the cursor to the position it was on before the user changed to
> per-record view.)
>
> I have to "manually" keep track of the cursor position, but in some
> cases it would definitely be easier to just query the current cursor
> position directly from the database and later use "MOVE ABSOLUTE" to
> rewind it to that position. That could be achieved e.g. by a
> hypothetical "TELL <cursor-name>" command. It does, however, not exist
> and I have not found an alternative. Is there a way to query the
> current cusros position at all? If not, does a TELL command sound like
> a good or bad idea?
>

It sounds like good idea.

Do we need a new statement? We can implement returning the position to MOVE
statement. It returns a delta, but it can returns a absolute position too.

Regards

Pavel

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