oops, should be > not <
:o)
select a.call_start, count(b.call_start) interruptions
from phone_call a, phone_call b
where a.call_start <= b.call_start and a.call_end > b.call_start
group by a.call_start
Cheers
Greg
-Original Message-
Sent: 15 August 2001 15:43
To: '[EMAIL PROTECTED]'
1. Create table CC with 2 fields: DT DATE, CALL_COUNT NUMBER .
2. Fill table CC with tuples with DT started from MIN(CALL_START) up to
MAX(CALL_END) and CALL_COUNT = 0. Step of DT value is 1 minute (or second =
36mil tuples/year).
3. for every tuple in a table of phone calls update table CC an
Give me some time :-)))
Jan Pruner
Dne st 15. srpen 2001 12:40 jste napsal(a):
> Dear gurus !
> I have a table of phone calls , 2 fields : CALL_START DATE ,
> CALL_END DATE .
> I need an SQL statement or a PL/SQL block to calculate the maximum
> number of SIMULTANIOUS phone conver
Dear gurus !
I have a table of phone calls , 2 fields : CALL_START DATE ,
CALL_END DATE .
I need an SQL statement or a PL/SQL block to calculate the maximum
number of SIMULTANIOUS phone conversations.
Consider there are 4 calls ,
one started at 12:10 and ended at 12:40
