Re: [HACKERS] ERROR: failed to find conversion function from "unknown" to text

On Tue, Jan 6, 2009 at 7:18 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:

> "Gurjeet Singh" <singh(dot)gurjeet(at)gmail(dot)com> writes:
> >> This is a horrendously bad idea; it will bite your *ss sooner or later,
> >> probably sooner.
>
> > Can you please let us know how this would be problematic?
>
> The point is that it's going to have unknown, untested effects on the
> default coercion rules, possibly leading to silent changes in the
> behavior of queries that used to work. If you'd rather retest every one
> of your other queries than fix this one, then go ahead.
>
>
Changing the query is an option not given to us. It is being migrated from a
BigDB.

I was working on these solutions assuming that these are workarounds to a
bug. But from your mails, it seems that it is an expected behaviour; is it?

If we consider the second branch of UNION ALL of both the queries above, if
"select '' " yields a text column, then so should a "select * from (select
'')".

Its not exactly a bug, but sure is a problem that we should try to resolve.

Thanks and best regards,
--
gurjeet[(dot)singh](at)EnterpriseDB(dot)com
singh(dot)gurjeet(at){ gmail | hotmail | indiatimes | yahoo }.com

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