Re: interval typmodout is broken

Tom Lane wrote:
> Alvaro Herrera <alvherre(at)2ndquadrant(dot)com> writes:
> > I just noticed when working on DDL deparsing that the typmodout routine
> > for intervals is broken. The code uses
>
> > if (precision != INTERVAL_FULL_PRECISION)
> > snprintf(res, 64, "%s(%d)", fieldstr, precision);
> > else
> > snprintf(res, 64, "%s", fieldstr);
>
> > which puts the parenthised number after the textual name; but the
> > grammar only takes it the other way around.
>
> You sure about that? The grammar for INTERVAL is weird. I believe
> the output we're trying to produce here is something like
>
> INTERVAL HOUR TO SECOND(2)
>
> where "fieldstr" would be " HOUR TO SECOND" and "precision" would
> give the fractional-second precision.

Well, I tested what is taken on input, and yes I agree the grammar is
weird (but not more weird than timestamp/timestamptz, mind). The input
function only accepts the precision just after the INTERVAL keyword, not
after the fieldstr:

alvherre=# create table str (a interval(2) hour to minute);
CREATE TABLE

alvherre=# create table str2 (a interval hour to minute(2));
ERROR: syntax error at or near "("
LÍNEA 1: create table str2 (a interval hour to minute(2));
^

--
Álvaro Herrera http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Training & Services