Robert Haas <robertmhaas@gmail.com> writes:
> Now, this case is a little trickier. If we called it simply
> parallel_degree rather than max_parallel_degree, then it would have
> the same name as the reloption. But the reloption sets an exact
> value, and the GUC sets a cap, which is a significant difference.
The reloption does not set an exact value, according to the code:
/* * Use the table parallel_degree, but don't go further than * max_parallel_degree. */
parallel_degree = Min(rel->rel_parallel_degree, max_parallel_degree);
although the existing documentation for it is so vague that you
couldn't tell from that.
regards, tom lane