Improve dblink error message when remote does not provide it
When dblink or postgres_fdw detects an error on the remote side of the
connection, it will try to construct a local error message as best it
can using libpq's PQresultErrorField(). When no primary message is
available, it was bailing out with an unhelpful "unknown error". Make
that message better and more style guide compliant. Per discussion
on hackers.
Backpatch to 9.2 except postgres_fdw which didn't exist before 9.3.
Discussion: https://postgr.es/m/19872.1482338965%40sss.pgh.pa.us
Branch
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REL9_4_STABLE
Details
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http://git.postgresql.org/pg/commitdiff/0f5b1867c2e6b752336f0b32d05f94c424664f79
Modified Files
--------------
contrib/dblink/dblink.c | 2 +-
contrib/postgres_fdw/connection.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
