Postgres Pro
Downloads
Home   >   mailing lists

Thread: work hour calculations

work hour calculations

From
novice
Date:
Hello All,

SELECT notification_time, finished_time, sum(finished_time -
notification_time) as actual
FROM log
GROUP BY notification_time, finished_time;

gives me:

   notification_time    |     finished_time      |     actual
------------------------+------------------------+-----------------
 2007-07-06 15:50:00+10 | 2007-07-09 07:10:00+10 | 2 days 15:20:00
 2007-07-07 12:30:00+10 | 2007-07-09 07:20:00+10 | 1 day 18:50:00


How can write a query to calculate the duration using custom work
hours which is Monday 7am /  Friday 5pm?

The result I'm expecting for the above to be

   notification_time    |     finished_time      |     actual
------------------------+------------------------+-----------------
 2007-07-06 15:50:00+10 | 2007-07-09 07:10:00+10 | 00:20:00
 2007-07-07 12:30:00+10 | 2007-07-09 07:20:00+10 | 00:20:00

Thanks.

Re: work hour calculations

From
novice
Date:
correction:

> The result I'm expecting for the above to be
>
>    notification_time    |     finished_time      |     actual
> ------------------------+------------------------+-----------------
   2007-07-06 15:50:00+10 | 2007-07-09 07:10:00+10 | 01:20:00
>  2007-07-07 12:30:00+10 | 2007-07-09 07:20:00+10 | 00:20:00
>

Re: work hour calculations

From
"Raj A"
Date:
correction:

> The result I'm expecting for the above to be
>
>    notification_time    |     finished_time      |     actual
> ------------------------+------------------------+-----------------
>  2007-07-06 15:50:00+10 | 2007-07-09 07:10:00+10 | 01:20:00
>  2007-07-07 12:30:00+10 | 2007-07-09 07:20:00+10 | 00:20:00

Re: work hour calculations

From
"Filip Rembiałkowski"
Date:
2007/9/5, Raj A <raj.ayappan@gmail.com>:
> correction:
>
> > The result I'm expecting for the above to be
> >
> >    notification_time    |     finished_time      |     actual
> > ------------------------+------------------------+-----------------
> >  2007-07-06 15:50:00+10 | 2007-07-09 07:10:00+10 | 01:20:00
> >  2007-07-07 12:30:00+10 | 2007-07-09 07:20:00+10 | 00:20:00

Could you please show the data structures ( create table commmands +
ane constraints you have )?

If you do this, you have much bigger chance of getting an answer :)



--
Filip Rembiałkowski

Re: work hour calculations

From
novice
Date:
On 07/09/2007, Filip Rembiałkowski <plk.zuber@gmail.com> wrote:
> 2007/9/5, Raj A <raj.ayappan@gmail.com>:
> > correction:
> >
> > > The result I'm expecting for the above to be
> > >
> > >    notification_time    |     finished_time      |     actual
> > > ------------------------+------------------------+-----------------
> > >  2007-07-06 15:50:00+10 | 2007-07-09 07:10:00+10 | 01:20:00
> > >  2007-07-07 12:30:00+10 | 2007-07-09 07:20:00+10 | 00:20:00
>
> Could you please show the data structures ( create table commmands +
> ane constraints you have )?
>
> If you do this, you have much bigger chance of getting an answer :)

sure

create table log
(
id integer PRIMARY KEY,
notification_time timestamp with time zone,
finished_time timestamp with time zone
);

INSERT INTO log values (1, '2007-07-06 15:50', '2007-07-09 07:10');
INSERT INTO log values (2, '2007-07-07 12:30', '2007-07-09 07:20');

SELECT notification_time, finished_time, sum(finished_time -
notification_time) as actual
FROM log
GROUP BY notification_time, finished_time;

Re: work hour calculations

From
"Filip Rembiałkowski"
Date:
2007/9/9, novice <user.postgresql@gmail.com>:
> > > > The result I'm expecting for the above to be
> > > >
> > > >    notification_time    |     finished_time      |     actual
> > > > ------------------------+------------------------+-----------------
> > > >  2007-07-06 15:50:00+10 | 2007-07-09 07:10:00+10 | 01:20:00
> > > >  2007-07-07 12:30:00+10 | 2007-07-09 07:20:00+10 | 00:20:00
> >
>
> create table log
> (
> id integer PRIMARY KEY,
> notification_time timestamp with time zone,
> finished_time timestamp with time zone
> );
>
> INSERT INTO log values (1, '2007-07-06 15:50', '2007-07-09 07:10');
> INSERT INTO log values (2, '2007-07-07 12:30', '2007-07-09 07:20');
>
> SELECT notification_time, finished_time, sum(finished_time -
> notification_time) as actual
> FROM log
> GROUP BY notification_time, finished_time;
>

OK. so I have bad news for you: with such structure, you will have to
write some function to calculate work time spent for each task.

general algorithm would be similar to

* take the notification time
* take the finished_time
* set pointer := notif. time
* set actual := 0
* while there is any weekend between the pointer and  finished_time,
do the following
** set actual := actual + ( weekend begin - pointer )
** move pointer to the next monday morning
* set actual := actual + ( finished_time - pointer )

BUT:
this is ugly.
do you always assume that people are doing ONLY one task at a time?

maybe think of representing work sheets in the database?

maybe think of adding "work_time" field to your table (why not trust
people, they know best)

maybe the application you use for entering data could give some "hint"
basing on above algo.


good luck,



--
Filip Rembiałkowski