Re: autonomous transactions

Robert Haas wrote:
> On Thu, Sep 16, 2010 at 5:19 AM, Dimitri Fontaine <dfontaine@hi-media.com> wrote:
>> I think they call that dynamic scope, in advanced programming
>> language. I guess that's calling for a quote of Greenspun's Tenth Rule:
>>
>>  Any sufficiently complicated C or Fortran program contains an ad hoc
>>  informally-specified bug-ridden slow implementation of half of Common
>>  Lisp.
>>
>> So the name of the game could be to find out a way to implement (a
>> limited form of) dynamic scoping in PostgreSQL, in C, then find out all
>> and any backend local variable that needs that to support autonomous
>> transactions, then make it happen… Right?
> 
> Interestingly, PostgreSQL was originally written in LISP, and there
> are remnants of that in the code today; for example, our heavy use of
> List nodes.  But I don't think that has much to do with this project.
> I plan to reserve judgment on the best way of managing the relevant
> state until such time as someone has gone to the trouble of
> identifying what state that is.

It would probably do Pg some good to try and recapture its functional language 
roots where reasonably possible.  I believe that, design-wise, functional 
languages really are the best way to do object-relational databases, given that 
pure functions and immutable data structures are typically the best way to 
express anything one would do with them. -- Darren Duncan