Mark Priest <mark.priest@computer.org> writes:
> However, I am still curious as to why I am getting an out of memory
> error. I can see how the performance might be terrible on such a
> query but I am surprised that postgres doesn't start using the disk at
> some point to reduce memory usage. Could it be that postgres tries
> to keep temp tables in memory?
You're running out of memory in the planner, long before execution ever
happens. (This is apparent from the memory map, but I also verified it
with a debugger yesterday.) There really isn't any alternative but to
change the form of the query or upgrade to a newer PG.
regards, tom lane