Oracle BI Answers Problem Using Group By condition.

Question

Hi All,
I'm new to Oracle BI. i have a requirment to count the number of opened request and number of closed request(month wise) from a table which have fallowing columns:
Date logged(Date) Status(character) Date closed(date)
8/12/2008 open null
8/19/2008 closed 8/21/2008
I also neeed the total closed request for a particular month irrespective of the opened month.( eg. if a request was raised in Apr and was closed in Aug shoulb be counted.)
For this requirment i modified the select query:
SELECT new_event.Month saw_0, new_event.opened saw_1, new_event.closed saw_2, new_event.Cmonth saw_3 FROM
(SELECT MONTHNAME(Events."Logged Date/time") as MONTH , COUNT(Events.Status) as opened,0 as closed,0 as Cmonth FROM Incidents WHERE ("Assigned Service Dept"."Assigned SVD" = 'WHG DSG SUPPORT') AND (Events.Status IN ('Open', 'Closed')) GROUP BY MONTHNAME(Events."Logged Date/time")
UNION
SELECT MONTHNAME(Events."Logged Date/time") as MONTH ,0 as Opened, COUNT(Events.Status) as closed,0 as Cmonth FROM Incidents WHERE ("Assigned Service Dept"."Assigned SVD" = 'WHG DSG SUPPORT') AND Events.Status = 'Closed' GROUP BY MONTHNAME(Events."Logged Date/time")
UNION
SELECT MONTHNAME(Events."Closure Date") as MONTH ,0 as Opened,0 as closed, COUNT(Events.Status) as Cmonth FROM Incidents WHERE ("Assigned Service Dept"."Assigned SVD" = 'WHG DSG SUPPORT') AND Events.Status = 'Closed' GROUP BY MONTHNAME(Events."Closure Date")) new_event
ORDER BY saw_0, saw_2, saw_3
Using This query i'm able to get the fallowing result set.
Month opened closed Cmonth
Apr 25 0 0
0 0 27
0 25 0
Aug 27 0 0
0 0 21
0 10 0
So I want to do a group by month and sum of closed, opened and cmonth column.
But when i add the group by condition i'm getting the error as "GROUP BY Condition Needed"
Thanks,
Sumit

Answer 1

Ignore the SQL let Analytics handle that for you, the key here is to get your model correct.
You need a Time Dimension (ie. a table full of calendar dates) which you join to your Fact table date columns in the Physical layer.
In the logical layer fact table you should have two columns #Open and # Closed - these will be based on a case condition sum aggregate ie.
No. Open
CASE WHEN closed_date IS NULL THEN 1
ELSE 0
END
No. Closed
CASE WHEN closed_date IS NOT NULL THEN 1
ELSE 0
END
If you then make sure you join your Time Dimension (create an alias for each instance) to the open and closed dates you'll be able to have a count of the items closed by Year/Month/Week/Date etc...