On 2022-Oct-26, Alvaro Herrera wrote:
> On 2022-Oct-25, Finnerty, Jim wrote:
>
> > Or if you know the frequencies of the highly frequent values of the
> > partitioning key at the time the partition bounds are defined, you
> > could define hash ranges that contain approximately the same number of
> > rows in each partition. A parallel sequential scan of all partitions
> > would then perform better because data skew is minimized.
>
> This sounds very much like list partitioning to me.
... or maybe you mean "if the value is X then use this specific
partition, otherwise use hash partitioning". It's a bit like
multi-level partitioning, but not really.
(You could test this idea by using two levels, list partitioning on top
with a default partition which is in turn partitioned by hash; but this
is unlikely to work well for large scale in practice. Or does it?)
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Álvaro Herrera 48°01'N 7°57'E — https://www.EnterpriseDB.com/
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