Re: array_agg() NULL Handling - Mailing list pgsql-hackers

From Pavel Stehule
Subject Re: array_agg() NULL Handling
Date
Msg-id AANLkTi=vAhu6Q+579pXWaXe-6qyXvTA0+F7t3UA447MU@mail.gmail.com
Whole thread Raw
In response to Re: array_agg() NULL Handling  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: array_agg() NULL Handling  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
2010/9/1 Tom Lane <tgl@sss.pgh.pa.us>:
> "David E. Wheeler" <david@kineticode.com> writes:
>> On Sep 1, 2010, at 11:09 AM, Pavel Stehule wrote:
>>> Then you can eliminate NULLs with simple function
>
>> Kind of defeats the purpose of the efficiency of the aggregate.
>
> Well, you can build your own version of array_agg with the same
> implementation, except you mark the transition function as strict ...
>

I am checking this now, and it is not possible - it needs a some
initial value and there isn't possible to set a "internal" value.
probably some C coding is necessary.

Regards

Pavel

>                        regards, tom lane
>


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