Ron Peacetree <rjpeace(at)earthlink(dot)net> writes:
> 2= No optimal external sorting algorithm should use more than 2 passes.
> 3= Optimal external sorting algorithms should use 1 pass if at all possible.
A comparison-based sort must use at least N log N operations, so it
would appear to me that if you haven't got approximately log N passes
then your algorithm doesn't work.
regards, tom lane
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