About aggregates...

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От Michael Giannakopoulos
Тема About aggregates...
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Msg-id CAAADf7LtTqvAwZLdp49o5A_e3nTWDmFuEJ8r0FfgVdeWebFQKQ@mail.gmail.com
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Ответы Re: About aggregates...  (Ondrej Ivanič <ondrej.ivanic@gmail.com>)
Re: About aggregates...  ("David Johnston" <polobo@yahoo.com>)
Re: About aggregates...  ("Albe Laurenz" <laurenz.albe@wien.gv.at>)
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Hello guys,

I would like to ask if there is any way to make an aggregate function to take a set of tuples as an input variable. I know that an actual aggregate function receives each tuple one at a time and process it on the fly. However I want to store tuples in an incremental fashion so as to process them in a batch approach in the finalaggr function. Think for example implementing logistic regression (which is an OLAP query by its nature). I want to support it with the current features that PostgreSQL provides from which the closest feature is an aggregate. However an aggregate function feeds me one a tuple for each call, but I would like to have access to a batch of tuples per function call. Is there any possible way to perform something like this?

Thank you very much for your time,
Michael 

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