Re: Nested transactions: low level stuff

Hiroshi Inoue wrote:
> Tom Lane wrote:
> > 
> > Hiroshi Inoue <Inoue@tpf.co.jp> writes:
> > > Sorry I have a basic question.
> > > Was there any consensus we would introduce nested transactions
> > > (or savepoints) in the way currently discussed ?
> > 
> > I think we are a long way from saying we can or will actually do it.
> > Error handling and resource management (eg locks) are a couple of other
> > huge cans of worms that have yet to be opened.  But certainly a solid
> > design for the transaction logging and tuple validity checking is a
> > necessary step.
> 
> Is the way to undo data rejected already ?

You mean abort subtransactions?  Each subtransaction gets its own
transaction id, so we just mark that as aborted --- there is no undo of
tuples, though I had originally suggested that approach years ago.

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