Foreign Key Deferrable Misunderstanding or Bug?
Why does the attached script fail with a foreign key constraint violation?
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Attachments:
test-fk-def.sqltext/x-sql; name=test-fk-def.sqlDownload
Paul Rogers <progers@sparkbase.com> writes:
Why does the attached script fail with a foreign key constraint violation?
The ON DELETE RESTRICT is why. Per the fine manual:
[RESTRICT] is the same as NO ACTION except that the check is not
deferrable.
It's a bit odd, but that's the best interpretation we can make of the
spec's wording about how this should work.
regards, tom lane
On Thu, 6 Aug 2009, Paul Rogers wrote:
Why does the attached script fail with a foreign key constraint violation?
Referential actions are not deferred when a constraint is marked
deferrable (as that appears to be what the spec wants), so ON DELETE
RESTRICT will still fail on the statement, while ON DELETE NO ACTION (ie,
only check at constraint check time) should wait to the end.