Re: Postgres_fdw join pushdown - wrong results with whole-row reference

On 2016/06/27 18:56, Ashutosh Bapat wrote:
> On Mon, Jun 27, 2016 at 3:06 PM, Etsuro Fujita
> <fujita(dot)etsuro(at)lab(dot)ntt(dot)co(dot)jp <mailto:fujita(dot)etsuro(at)lab(dot)ntt(dot)co(dot)jp>> wrote:

> I found another bug in error handling of whole-row references in
> join pushdown; conversion_error_callback fails to take into account
> that get_relid_attribute_name(Oid relid, AttrNumber attnum) can't
> handle whole-row references (ie, attnum=0), in which case that would
> cause cache lookup errors. Attached is a small patch to address
> this issue.

> Do you have any testcase reproducing the bug here? It would be good to
> include that test in the regression.

Done.

> There is a always a possibility that a user would create a table (which
> can be used as target for the foreign table) with column named
> 'wholerow', in which case s/he will get confused with this error message.

By grepping I found that there are error messages that use "whole-row
table reference", "whole-row reference", or "wholerow", so the use of
"wholerow" seems to me reasonable. (And IMO I think "wholerow" would
most likely fit into that errcontext().)

Best regards,
Etsuro Fujita