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Message-ID: <464ece4e-fabb-ddac-60da-897493c4476d@enterprisedb.com>
Date: Wed, 18 Jan 2023 16:06:02 +0100
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Subject: Re: ANY_VALUE aggregate
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To: Vik Fearing <vik@postgresfriends.org>,
 PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
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 <bf4652c9-0283-af94-31c5-3ac936f07878@postgresfriends.org>
From: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
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On 05.12.22 21:18, Vik Fearing wrote:
> On 12/5/22 15:57, Vik Fearing wrote:
>> The SQL:2023 Standard defines a new aggregate named ANY_VALUE.  It 
>> returns an implementation-dependent (i.e. non-deterministic) value 
>> from the rows in its group.
>>
>> PFA an implementation of this aggregate.
> 
> Here is v2 of this patch.  I had forgotten to update sql_features.txt.

In your patch, the documentation says the definition is any_value("any") 
but the catalog definitions are any_value(anyelement).  Please sort that 
out.

Since the transition function is declared strict, null values don't need 
to be checked.  I think the whole function could be reduced to

Datum
any_value_trans(PG_FUNCTION_ARGS)
{
     PG_RETURN_DATUM(PG_GETARG_DATUM(0));
}