Re: BUG #2905: min and max return incorrect text type

Alvaro Herrera wrote:
> Adriaan van Os wrote:
> > Tom Lane wrote:
> > >Bruce Momjian <bruce(at)momjian(dot)us> writes:
> > >>Peter Eisentraut wrote:
> > >>>Aside from the apparent discrepancy between the documentation and the
> > >>>actual behavior, is there an actual use case where this is a problem?
> > >
> > >>No, I don't think so, and I am reluctant to adjust the documentation to
> > >>say "or similar".
> > >
> > >The documentation is correct as it stands: max(text) returns text.
> > >Adriaan's complaint about max(varchar) is off base because there is
> > >no such function.
> >
> > No, the documentation says that the Argument Type of max and min can be
> > "any array, numeric, string, or date/time type" and that the Return type is
> > the "same as argument type". The functions min and max applied to a field
> > of type varchar return a function result of type text. So, if a
> > max(varchar) function is missing and the cause of the text result type is
> > implicit type casting, then the fact that there is no max(varchar) function
> > is exactly the bug.
>
> Do you have a specific situation on which this causes a problem for you?
> I mean, are you asking because it really bugs you, or just for the sake
> of being pedantic?

And what suggestion do you have for a change? How would you like the
documentation wording changed?

--
Bruce Momjian bruce(at)momjian(dot)us
EnterpriseDB http://www.enterprisedb.com

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