On Sun, Dec 18, 2011 at 10:28, Gianni Ciolli
<gianni.ciolli@2ndquadrant.it> wrote:
> http://wiki.postgresql.org/wiki/Autonomous_subtransactions
>
> It is meant to be an ongoing project, requesting comments and
> contributions, rather than a conclusive document.
In addition to what Jim Nasby said, this proposal seems a bit
inflexible. In particular:
1. It limits us to exactly 2 autonomous transactions at any time (the
main one and the "subtransaction").
2. There's no reason why two autonomous transactions should have a
"main / sub" relationship. They are autonomous -- they should not
depend on the state of the "outer" transaction.
Now, the initial implementation may well have such limits, but I think
you should design your proposal to accommodate the above two features
in the future without having to redesign the syntax.
Maybe look at SAVEPOINTs for inspiration. There can be multiple
savepoints in a single transaction, and they can be released/rolled
back to, at any time.
Regards,
Marti