Re: BUG #1871: operations with data types

Added to TODO:

o Fix SELECT INTERVAL '1' MONTH;

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Tom Lane wrote:
> Michael Fuhr <mike(at)fuhr(dot)org> writes:
> > I just noticed something in PostgreSQL that might be considered
> > surprising (although I do see "Add ISO INTERVAL handling" in the
> > TODO list):
>
> > test=> select interval '1' month;
> > interval
> > ----------
> > 00:00:00
> > (1 row)
>
> > What's the parser doing here?
>
> Not getting it right ;-). Trying this in historical versions is
> amusing:
>
> 7.0:
> regression=# select interval '1' month;
> ERROR: parser: parse error at or near "month"
>
> 7.1:
> regression=# select interval '1' month;
> ERROR: Bad interval external representation '1'
>
> 7.2:
> regression=# select interval '1' month;
> interval
> ----------
> 00:00
> (1 row)
>
> 7.3:
> regression=# select interval '1' month;
> interval
> ----------
> 00:00:01
> (1 row)
>
> 7.4 and up:
> regression=# select interval '1' month;
> interval
> ----------
> 00:00:00
> (1 row)
>
> What is happening in the current versions is that coerce_type thinks
> it can coerce the literal string to interval without supplying the
> modifier, and then use interval_scale() to apply the typmod. This
> works OK for most of the data types, but not for interval it seems...
>
> Basically the support for these weird syntaxes is something that Tom
> Lockhart never finished, and no one has bothered to pick up the work
> since he left the project.
>
> regards, tom lane
>
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