How to get business days or hours between two dates

Question

How can I calculate business hours or days between two dates in oracle 10g?

For example we have two dates; 14/08/2012 9:30 and 16/08/2012 12:00 And we have working h

Answer 1

I just did something like that. Here is an sql code piece to calculate the work done between stime and etime by employees in a table T

create table t ( NAME varchar(50), stime date, etime date, clockin number,clockout number );
insert into t values ( 'JOHN', to_date( '18/12/2003 11:40','dd/mm/yyyy hh24:mi'), to_date( '22/12/2003 14:00', 'dd/mm/yyyy hh24:mi'),8, 17 );
insert into t values ( 'JOHN', to_date( '19/12/2003 13:40','dd/mm/yyyy hh24:mi'), to_date( '21/12/2003 15:00', 'dd/mm/yyyy hh24:mi'),8, 17 );
insert into t values ( 'TOM', to_date( '19/12/2003 13:40','dd/mm/yyyy hh24:mi'), to_date( '21/12/2003 15:00', 'dd/mm/yyyy hh24:mi'),8, 17 );


with oo as (SELECT LEVEL-1 rn FROM dual CONNECT BY LEVEL <= 365) --JUST A TABLE WITH INTEGER RECORDS FROM 1 To 365 
select
t.NAME ,sum(least( trunc(stime)+18.5/24+rn, etime )-greatest( stime, trunc(stime)+9.5/24+rn))*24 as WorkHours -- Get workhours between 09:30-18:30 
from oo
inner join t on oo.rn < (trunc(etime)-trunc(stime)+1) 
      and to_char(stime+rn,'Dy') not in ( 'Sat', 'Sun' )  --For eliminating Weekends
      and to_char(trunc(stime)+rn,'DD.MM')  != '04.07'   -- For eliminating Holidays
group by t.NAME 

You can delete the group by line and remove the sum function to see how it works by generating rows for each day worked.