What to do when OBIEE fact tables do not join to all dimension tables?
Here using the Sh Schema to Explain the above
Scenario
The Step By Step Process:
Import Products,costs,sales,customers
Tables From SH Schema….
Physical Diagram Joins between Facts and
Dimensions
In The Above We don’t have join between
customers and costs….when we try to get the data,
From this in Answers it will be like this
In one way this result is correct, because
there is no join between customer and costs…
So the BI server has fired the Database
with the following Query
select
distinct D1.c1 as c1,
D1.c2 as c2,
cast(NULL as DOUBLE PRECISION ) as c3
from
(select distinct T78.CUST_FIRST_NAME as
c1,
T102.PROD_CATEGORY as c2
from
CUSTOMERS T78,
PRODUCTS T102,
SALES
T125
where
( T78.CUST_ID = T125.CUST_ID and T102.PROD_ID = T125.PROD_ID )
) D1
order
by c1, c2
Though we Have not selected any
column from sales the bi server has
Directed to aggregate based on
sales….
In order to Fetch the Data using
customers and costs we need to set Physically complex join or we can set
content level to Total
In physical layer, by making the
condition always true…
Physical Diagram Will be Like this
In Bmm Layer Make Sure to Create
Hierarchies for the dimensions,Don’t set any Level Based Measures
Drag and drop in Presentation Layer
Check for global consistency and
save it. Run the Bi Server and Presentation
services And check the result..
Now, This works….Here The Important
Point to remember is the output that has got is an Cartesian product….Generally
Don’t go for this because it will cause some performance issues…..
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