[postgis-devel] Re: [Bizgres-general] Bizgres MPP and PostGIS

[Markus Schaber]

Hi, Luke,

Luke Lonergan wrote:

>> However, to be parallelizable, at least aggregates will need special
>> support, to merge the distributed states, I presume.
> As of recently, we allow user defined aggregates per the PostgreSQL spec.
> These can be parallel - which is critical for large data.  We routinely use
> 64+ CPUs to compute aggregates, which allows us to scale to tens of TB.

How do you merge the distributed states? Does the user have to define a
special merge function?


Thanks,
Markus


-- 
Markus Schaber | Logical Tracking&Tracing International AG
Dipl. Inf.     | Software Development GIS

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