Subject: Re: Need query
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From: Thomas Kellerer <shammat@gmx.net>
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Date: Sun, 18 Jul 2021 16:54:08 +0200
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Caetano Traina Junior schrieb am 18.07.2021 um 15:19:>
>> Em s=C3=A1b., 17 de jul. de 2021 =C3=A0s 05:33, Thomas Kellerer <shamma=
t@gmx.net <mailto:shammat@gmx.net>> escreveu:
>>     And before you ask: it's not really possible to make this dynamic, =
so that the number
>>     of columns "automagically" increases when you have more fruits. One=
 fundamental
>>     restriction of the SQL language is that the number and types of all=
 columns
>>     must be known to the database when the query is parsed. It can't ch=
ange
>>     the columns as a result of the query itself.

> Nonetheless, it is always possible to write a dynamic SQL (and best
> yet, inside a plpgsql function) to "automagically handle more
> fruits..."

Even if you create a function that uses dynamic SQL, you still have to
specify each output column "manually" when calling the function.
So that doesn't really buy you anything.