Thread: pgsql: Fix documentation for dblink_error_message() return value

Fix documentation for dblink_error_message() return value

The dblink documentation claims that an empty string is returned if there
has been no error, however OK is actually returned in that case. Also,
clarify that an async error may not be seen unless dblink_is_busy() or
dblink_get_result() have been called first.

Backpatch to all supported branches.

Reported-by: realyota
Backpatch-through: 9.4
Discussion: https://postgr.es/m/153371978486.1298.2091761143788088262@wrigleys.postgresql.org

Branch
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REL9_4_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/64f6a65a00b0b6d768fc3fc49047524f4f99a54d

Modified Files
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doc/src/sgml/dblink.sgml | 16 +++++++++++++++-
1 file changed, 15 insertions(+), 1 deletion(-)