I have written the attached patch which I think does what you suggested.
I found all the places where we disallowed 24:00:00, and make it valid,
including nabstime.c.
test=> select '24:00:00'::time(0);
time
----------
24:00:00
(1 row)
test=> select '24:00:01'::time(0);
ERROR: date/time field value out of range: "24:00:01"
---------------------------------------------------------------------------
Tom Lane wrote:
> Inserting into a time field with limited precision rounds off, which
> is good except for this case:
>
> regression=# select '23:59:59.9'::time(0);
> time
> ----------
> 24:00:00
> (1 row)
>
> This is bad because:
>
> regression=# select '24:00:00'::time(0);
> ERROR: date/time field value out of range: "24:00:00"
>
> which means that data originally accepted will fail to dump and reload.
>
> I see this behavior in all versions back to 7.3. 7.2 was even more
> broken:
>
> regression=# select '23:59:59.9'::time(0);
> time
> ----------
> 00:00:00
> (1 row)
>
> I think the correct behavior has to be to check for overflow again
> after rounding off. Alternatively: why are we forbidding the value
> 24:00:00 anyway? Is there a reason not to allow the hours field
> to exceed 23?
>
> regards, tom lane
>
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