Importance of Global Consistency check

Question

Hello,
I have always checked my rpd for global consistency without knowing the actual meaning behind it. But last night I created a logical column with the following expression:
max(VALUEOF(NQ_SESSION......))
basically i created an aggregation over a logical column that obtains its value from session variable. I know that if we need to use a column as an aggregation column we should use the aggregation tab in the column properties. When we choose an aggregation it disables the editable column formula field.
I put the above formula which violates the rule. The result is perfect so long as I don't check for global consistency. It throws an error that looks something like this:
[38083] The Attribute 'Acceptance Rate Target' defines a measure using an obsolete method.
The question is.. what is the significance of global consistency check.. and what is the consistency criteria.. and is it ok to save the rpd without checking for global consistency (yes this does not cause the BI server to crash when trying to start)
Thanks

Answer 1

First, forget about the variable approach.
Now you need to do the following steps:
1) Import the table to the physical layer
2) Create logical table in existing Business Model in BMM layer with the imported table as logical table source
3) Create another logical table in existing Business Model in BMM layer with the imported table as logical table source
4) Create complex join between both table, now you will get one logical dimension table and one logical fact table
5) In the logical fact table you need to select the column ("Target") and add an aggregation rule, like MAX or MIN
6) Assuming you have a hierarchy for every dimension in your BMM layer, you need to set the logical levels of the new measure to the Grand Total Level of each dimension hierarchy.
By doing this, you get a "level based measure", for more info: read this:
http://oraclebizint.wordpress.com/2007/12/03/oracle-bi-ee-101332-level-based-measures-lbms/
By setting all logical levels to the grand total level, the measure will be "immune" for all dimensions used in your report.
So when you have a report like
Month__Actual___Target
The BI Server will create two queries:
select month, sum(sales) from calendar, sales_table where calendar.id = sales_table.calendar_id
and
select max(value) from target_table
The BI Server will then stitch both results together.
Regards,
Stijn