Re: [SQL] datetime function

In SQL/92:

prova=> select CURRENT_TIME as now, time '18:50:00' - current_time as diff;
now |diff
--------+--------
18:47:48|00:02:12
(1 row)

To have this in PostgreSQL create a PL/pgSQL function like:

create function time_mi_time(time,time) returns timespan as
'
declare
i1 interval;
i2 interval;
begin
i1:= $1;
i2:= $2;
i1:=i1 - i2;
return i1;
end;
' language 'plpgsql';

create operator - (
leftarg=time,
rightarg=time,
procedure=time_mi_time,
commutator='-',
negator='+',
restrict=eqsel,
join=eqjoinsel
);

"Pham, Thinh" ha scritto:

> Is there any sql92 functions (not really essential) that calculates the
> timespan between 2 separate points in time? For example, i want to calculate
> the total minutes between 2:30pm and 3:30pm. There's a function like this in
> microsoft sql but i can't find it in postgres. Below is how it works in ms:
>
> DATEDIFF(minute, '14:30', '15:30')
>
> I looked at the "timespan" function but it's not the same one that i need.
> Thanks,
> Thinh

> --

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PostgreSQL 6.5.0 on i586-pc-linux-gnu, compiled by gcc 2.7.2.3
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Jose'