Re: why generated columsn cannot be used in COPY TO?

Am 06.10.23 um 15:47 schrieb Tom Lane:
> Luca Ferrari <fluca1978(at)gmail(dot)com> writes:
>> I'm wondering why in COPY TO (file or program) I cannot use generated
>> columns: since I'm pushing data out of the table, why they are not
>> allowed?
> There's a comment about that in copy.c:
>
> * We don't include generated columns in the generated full list and we don't
> * allow them to be specified explicitly. They don't make sense for COPY
> * FROM, but we could possibly allow them for COPY TO. But this way it's at
> * least ensured that whatever we copy out can be copied back in.

ha, as always: read the source ;-)

>
> Not sure how convincing that reasoning is, but it was at least
> thought about. I do agree with it as far as the default column
> list goes, but maybe we could allow explicit selection of these
> columns in COPY TO.

sounds okay

Andreas

--
Andreas Kretschmer - currently still (garden leave)
Technical Account Manager (TAM)
www.enterprisedb.com