Re: [PERFORM] Hash Anti Join performance degradation

Tom Lane-2 wrote:
> 
> It looks like it ought to be an O(N^2)
> situation, so the improvement should be noticeable but not amazing.
> 

Hm, the performance was reasonable again when doing a cluster...
So I believe this should be more a technical than an
algorithmical/complexity issue. Maybe it is the way the hashtable is built
and that order makes a difference in that case? In short: Why is clustered
data not affected?

Regards,
panam

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