Bruce Momjian <bruce(at)momjian(dot)us> writes:
> On Mon, Jul 4, 2016 at 12:09:32PM -0400, Tom Lane wrote:
>> Drop or rename your index named "concurrently".
>>
>> (PG 9.0 and up seem to quote that index name safely, but 8.4 doesn't,
>> and it's long out of support.)
> That is odd because pg_upgrade uses the _new_ 9.4 pg_dump to dump the
> old cluster.
Yeah, but pg_dump depends on the backend to do some of the work,
and 8.4 doesn't have quote-all-identifiers support.
regards, tom lane