Tom Lane wrote:
> The real point here is that omitting the per-command subtransaction
> ought to be a hidden optimization, not something that intrudes to the
> point of having unclean semantics when we can't do it.
Sorry to be stupid here, but I didn't understand this when it was 
disussed originally either. Why a subtransaction per command rather than 
one per function? If I've got this right, this is so the PL can tidy up 
behind itself and report/log an appropriate error?
--
   Richard Huxton
   Archonet Ltd