Re: BUG #18377: Assert false in "partdesc->nparts >= pinfo->nparts", fileName="execPartition.c", lineNumber=1943

I noticed further problems with this patch, and it turned out to have
other bugs that would manifest under very high concurrency of detach and
attach (I think the problem was a detach followed by an immediate attach
of the same partition, or perhaps it was an attach of a neighboring
partition), so I spent more time ironing those out and ended up with the
following, which I'm rather embarrased not to have had as the previous
version because it looks simpler and more obvious.

Unless further surprises arise soon, I'll push this soonish.

-- 
Álvaro Herrera         PostgreSQL Developer  —  https://www.EnterpriseDB.com/
"Ellos andaban todos desnudos como su madre los parió, y también las mujeres,
aunque no vi más que una, harto moza, y todos los que yo vi eran todos
mancebos, que ninguno vi de edad de más de XXX años" (Cristóbal Colón)