Re: BUG #4204: COPY to table with FK has memory leak

"Tom Lane" <tgl(at)sss(dot)pgh(dot)pa(dot)us> writes:

> Gregory Stark <stark(at)enterprisedb(dot)com> writes:
>> "Tom Lane" <tgl(at)sss(dot)pgh(dot)pa(dot)us> writes:
>>> This is expected to take lots of memory because each row-requiring-check
>>> generates an entry in the pending trigger event list.
>
>> Hm, it occurs to me that we could still do a join against the pending event
>> trigger list... I wonder how feasible it would be to store the pending trigger
>> event list in a temporary table instead of in ram.
>
> We could make that list spill to disk, but the problem remains that
> verifying the rows one at a time will take forever.

Well I was thinking if we did a join between a temporary table and the fk
target then it wouldn't have to be a one-by-one operation. It could be a merge
join if the planner thought that was better. How to get accurate stats into
the planner at that point would be a missing detail though.

--
Gregory Stark
EnterpriseDB http://www.enterprisedb.com
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