A difficult select

Question

Hi,
I have the following data from a schedule system
begin_time End_time status
============================
9:00 9:30 vacant
9:30 10:00 vacant
10:00 10:30 vacant
10:30 11:00 busy
11:00 11:30 busy
11:30 12:00 vacant
12:00 12:30 busy
12:30 13:00 vacant
how can I write 1 sql to display the busy hours any take the ending time of the resouces so the out put will be:-
begin_time End_time status
============================
10:30 11:30 busy
12:00 12:30 busy
note that 10:30-11:00 and 11:00-11:30 is merged as 1
or alternatively, I could also modify the script to display the vacant hours so that it will be:-
begin_time End_time status
============================
9:00 10:30 vacant
11:30 12:00 vacant
12:30 13:00 vacant
Again note that all the time for 9:00 - 10:30 are merged. But also note that the data is split according to continues availability of the time.
Does any one have any idea to help me to have 1 single sql to do this?
I am using oracle 8.0.5 server, so please don't advice me to use any oracle 9 and above commands.
Thanks

Answer 1

Hi Jonas,
Actually, I am doing a time table system for a college and the followings are some table
SQL> desc RESOURCE_DAY_TIME_SETUP
Name Null? Type
CAMPUS NOT NULL VARCHAR2(40)
RESOURCES_CATEGORIES NOT NULL VARCHAR2(40)
RESOURCES_CODE NOT NULL VARCHAR2(30)
TIME_FROM NOT NULL DATE
TIME_TO NOT NULL DATE
DAY NOT NULL VARCHAR2(10)
COLLEGE_REG_NO NOT NULL VARCHAR2(40)
DAY_CODE NOT NULL NUMBER(1)
TIME_ZONE NOT NULL NUMBER(2)
BUILDING_CODE NOT NULL VARCHAR2(40)
FLOOR_CODE NOT NULL VARCHAR2(40)
CLASS_ZONE NOT NULL NUMBER(2)
CAPACITY NOT NULL NUMBER(5)
SQL> desc RESOURCE_ACTIVITY_MASTER
Name Null? Type
CAMPUS NOT NULL VARCHAR2(40)
RESOURCES_CATEGORIES NOT NULL VARCHAR2(40)
RESOURCES_CODE NOT NULL VARCHAR2(30)
DAY NOT NULL VARCHAR2(10)
TIME_FROM NOT NULL DATE
TIME_TO NOT NULL DATE
ACTIVITY_SUBJECT NOT NULL VARCHAR2(20)
LECTURER_NAME NOT NULL VARCHAR2(30)
REMARKS VARCHAR2(10)
INTAKE_NUMBER NUMBER(10)
SEMESTER_NO NUMBER(5)
PERIOD_FROM NOT NULL DATE
PERIOD_TO NOT NULL DATE
COLLEGE_REG_NO NOT NULL VARCHAR2(40)
COURSE_CODE VARCHAR2(20)
CAPACITY NUMBER(5)
TIME_ZONE NUMBER(2)
DAY_CODE NUMBER(2)
STATUS VARCHAR2(1)
TT_LOCK VARCHAR2(1)
The setup table contains all the timing and the master table contains all the activity.
based on your example, i changed my sql to be:-
SELECT distinct rdts1.BUILDING_CODE Building,
rdts1.DAY,rdts1.RESOURCES_CODE Room,
TO_CHAR(min(rdts1.TIME_FROM), 'HH24:MI') "FROM",
TO_CHAR(rdts2.TIME_TO,'HH24:MI') "TO"
FROM RESOURCE_DAY_TIME_SETUP rdts1,RESOURCE_DAY_TIME_SETUP rdts2, RESOURCE_ACTIVITY_MASTER
WHERE RESOURCE_ACTIVITY_MASTER.CAMPUS(+) = rdts1.CAMPUS
AND rdts1.CAMPUS LIKE 'KL CAMPUS'
AND RESOURCE_ACTIVITY_MASTER.COLLEGE_REG_NO(+) LIKE '177263-T'
AND RESOURCE_ACTIVITY_MASTER.DAY(+) = rdts1.DAY
AND rdts1.DAY LIKE TO_CHAR(sysdate, 'DY')
AND RESOURCE_ACTIVITY_MASTER.RESOURCES_CODE(+) = rdts1.RESOURCES_CODE
AND TO_CHAR(RESOURCE_ACTIVITY_MASTER.TIME_FROM(+), 'HH24:MI') = TO_CHAR(rdts1.TIME_FROM, 'HH24:MI')
AND TO_CHAR(RESOURCE_ACTIVITY_MASTER.TIME_TO(+), 'HH24:MI') = TO_CHAR(rdts1.TIME_TO, 'HH24:MI')
AND RESOURCE_ACTIVITY_MASTER.PERIOD_FROM(+) <= sysdate
AND RESOURCE_ACTIVITY_MASTER.PERIOD_TO(+) >= sysdate
and resource_activity_master.status(+) like 'N'
and nvl(RESOURCE_ACTIVITY_MASTER.CAMPUS,'x') = 'x'
and exists
(select 'x' from RESOURCE_DAY_TIME_SETUP rdts3
where to_char((rdts3.time_from),'HH24:mi') > to_char((rdts1.time_from),'HH24:mi')
and not nvl(rdts1.campus,'x') = nvl(rdts3.campus,'x')
having TO_CHAR(rdts2.TIME_FROM, 'HH24:MI') = to_char(min(rdts3.time_from),'HH24:mi') )
and rdts1.RESOURCES_CODE = '2.04'
group by rdts2.TIME_TO, rdts1.BUILDING_CODE, rdts1.DAY,rdts1.RESOURCES_CODE
ORDER BY rdts1.BUILDING_CODE,
rdts1.DAY,
rdts1.RESOURCES_CODE,
TO_CHAR(min(rdts1.TIME_FROM), 'HH24:MI'),
TO_CHAR(rdts2.TIME_TO, 'HH24:MI')
and it is taking hours and yet the result comes out...
Any advices pls.
Thank you