|
Hi all,
Using 9.5.2.
Before you read I will apologise now, I do not have any prior experience with Cognos Report Studio so my definitions/terminology may be away off. We have an experienced BI developer here so don't worry - I'm not trying to do the BI side myself.
The scenario:
We have a system called Maximo that captures all of our committed costs. It does this task well, however trying to get a report out of this system is very painful. All of the data is currently saved to CSV files and loaded into SQL tables in our data-warehouse. We then have a TM1 model which has a much bigger scope, but a small part of it is bringing this commitment data in and holding it in a Commitment cube. This is a 12 dimension cube (1 time, 1 measures and 10 other) designed around the business requirements for how they wish to slice and dice all of their data. The cube size itself is not a problem for TM1. The data held in it is at a transactional level which again is a user requirement. Because this is essentially the only way to view the data in Maximo the requirement is to see transactional level data. A drill through to the SQL database was put forward and rejected.
We have an active form which is then published on TM1 Web which allows the users to view consolidated elements, drill down to leaf level elements etc. Apart from the Time dim being a page and the measures dim on the column, the otehr 10 dims were stacked up in the rows to give full visibility of the data. The response time is good.
However, we wanted to see if we could replicate this Commitment report in BI. As a business we already use BI on top of Cognos Analyst cubes and directly from SQL data-warehouse. This would be pretty much the first time that we were attempting to report directly from a TM1 cube.
The Problem:
In a nutshell the problem seems to be zero-suppression. The active form in TM1 handles this very well wish good response times. When trying to replicate the report in Report Studio we found the follwing:
1. If referencing a consolidated element in each of the 10 dimensions stacked up the report query ran within seconds and a report was ready.
2. If bringing "All" elements in on the same 10 dimensions the report query ran within seconds and a report was ready (although useless as the cube is so sparse - so is the report).
3. When attempting to suppress zero's the BI developer tried 2 different methods:
3a). Writing an MDX query for each cross point. This took about 15 mins to produce a report.
3b). Suppress zero's directly on the dimension (sorry I'm not sure what this is called). For one small dimensions (of the ten) this took a few seconds. For a big dimension it took a minute or so. For 3 dimensions together this took about 10 minutes to create a report.
Our conclusion:
Between the BI developer and I, the conclusion that we drew was that Report Studio does not handle querying transactional level data from a cube and zero suppressing it very efficiently. If the report was querying the SQL table directly it would be very quick. However to achieve this rolling up/drilling down the consolidated data would have to be stored in the SQL table too (which it currently isn't).
Any advice:
As always any advice would be greatly received. I appreciate that the first thought that might go through your mind is that transactional level data should not be held in a TM1 cube anyway or why are we trying to create a BI report from it!
Cheers |
|