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Old 04-10-2008, 11:10 AM
Greg Sabino Mullane
 
Posts: n/a
Default Re: Deferred FK / PK deletion problems


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Tom Lane wrote:
>> Came across an odd bug while dealing with deferred foreign keys.


> I'm not convinced this is a bug.


Can you elaborate on this? Am I doing something wrong in my app?
Someone on irc pointed out that this affects more than deferred
fk, but for my purposes, here's what's happening:

Table A has a primary key.
Table B references that primary key.

Process A periodically updates the table by doing
(basically) a delete all/insert new data, inside of
a transaction.

Process B is adding entries to table B.

If Process B happens in the "middle" of Process A,
the insert to B fails as it claims that the corresponding
row in table A does not exist.

Short of Process A grabbing an exclusive lock on the table, I
can't see a way around this. Feel free to punt this to
general if this is the expected behavior.

- --
Greg Sabino Mullane greg@turnstep.com
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http://biglumber.com/x/web?pk=2529DF...9B906714964AC8
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