Re: nested-xacts cursors (was Re: Performance with new

Tom Lane wrote:

> BTW, I've been more or less ignoring the nearby debate about whether
> cursors ought to roll back at subxact abort or not, because right now
> I don't know how to implement *either* behavior.  Unless we have
> credible theories about how to implement both, it's a bit useless to
> debate which is better.

If/when you have a choice -- the JDBC driver code gets easier if you 
don't roll back at abort. If rollback of cursor state can happen, then 
the driver will need to preserve client-side state associated with each 
cursor (i.e. the driver's idea of its position) at the start of each 
subtransaction so it can restore it on rollback -- or always use FETCH 
ABSOLUTE (which I think needs SCROLL cursors?)

-O