Re: Support UTF-8 files with BOM in COPY FROM - Mailing list pgsql-hackers

"David E. Wheeler" <david@kineticode.com> <CAJW2+qdYg1+xLaHDqnJs3AcKmCSVCDkv_LCAPWUtwmxL9dzVhQ@mail.gmail.com> writes:
> On Sep 25, 2011, at 9:58 PM, Itagaki Takahiro wrote:
>> I'm thinking about only COPY FROM for reads, but if someone wants to add
>> BOM in COPY TO, we might also support COPY TO WITH BOM for writes.

> I think it would have to be optional, since "some recipients of UTF-8 encoded data do not expect a BOM."

Putting a BOM into UTF8 data is flat out invalid per spec --- the fact
that Microsloth does it does not make it standards-conformant.

I think that accepting it on input can be sensible, on the principle of
"be liberal in what you accept", but the other side of that is "be
conservative in what you send".  No BOMs in output, please.
        regards, tom lane