Tom Lane wrote:
> > If you SELECT 'abc'::varchar(6)::varchar, the end type is varchar(6).
>
> Yeah, this is exactly what's happening --- if you look at gram.y,
> LOCALTIMESTAMP is expanded to "'now'::text::timestamp(6)". I am
> unconvinced that the (6) is a very good idea though. The code says
>
> /* SQL99 mandates a default precision of 6 for timestamp.
> * Also, that is about as precise as we will get since
> * we are using a microsecond time interface.
> * - thomas 2001-12-07
> */
> d->typmod = 6;
>
> but it doesn't seem to me to follow from what the spec says that we need
> to explicitly cast the result of now() to six places. As long as it's
> coming from gettimeofday it can't have more than 6 places anyway, and so
> we might as well save the extra coercion step. (The parser *will* tack
> on a separate coercion function call when presented with this parse
> tree.)
>
> In short, I'm inclined to remove the above-quoted lines, and similarly
> for CURRENT_TIME, CURRENT_TIMESTAMP, and LOCALTIME. Thoughts?
Agreed. That "6" bothered me too when I was cleaning up the timestamp
code a while back.
-- Bruce Momjian | http://candle.pha.pa.us pgman@candle.pha.pa.us | (610)
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