Royce Ausburn <royce.ml@inomial.com> writes:
> On 18/10/2011, at 1:00 PM, Robert Haas wrote:
>> I don't think it's a bug for it to work. It'd probably work in
>> PostgreSQL too, if you inserted (2) first and then (1). It's just
>> that, as Tom says, if you want it to be certain to work (rather than
>> depending on the order in which the rows are inserted), you need the
>> checks to be deferred.
> Do deferred checks such as this have a memory impact for bulk updates?
Yes indeed. That's why immediate check is the default.
regards, tom lane