On 7 June 2013 20:23, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> As for other databases, I suspect that ones that have parallel execution
> are probably doing it with a thread model not a process model.
Separate processes are more common because it covers the general case
where query execution is spread across multiple nodes. Threads don't
work across nodes and parallel queries predate (working) threading
models.
--Simon Riggs http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training & Services