BMM - Decision criteria on how to define LTS for a multi-source object

Question

I am curious to know what others use as their decision criteria when determining how to setup a BMM logical table that has multiple sources that map to multiple columns in the logical table.
For example,
If you have defined logical table Dim - Customer in the BMM that has 4 fields:
Dim - Customer
Customer Id
Customer Name
Customer Address
Customer Phone
The sources for this logical table from the physical layer are:
CUSTOMER (all customers exist here)
CUSTOMER_ADDRESS (A customer may or may not have an address, but can have only one address to simplify this conversation)
CUSTOMER_PHONE (A customer may or may not have a phone, but can have only one phone to simplify this conversation)
Field Mappings from Logical Table to Physical Table are:
Dim - Customer
Customer Id - CUSTOMER
Customer Name - CUSTOMER
Customer Address - CUSTOMER_ADDRESS
Customer Phone - CUSTOMER_PHONE
How would you setup the logical table and LTS's for this object in the BMM knowing the following requirements?:
1. The Address and Phone tables should only be joined in when fields from those tables are used in a report/query.
2. Since a customer may or may not have an address or phone, the BMM table needs to be setup such that adding those fields into a query will not filter all customers that dont have data for those fields, i.e. display null if it does not exist.
My initial approach for resolving this would be to set it up as follows:
A single Logical Table Source: LTS_CUSTOMER
Three Tables added to the LTS:
CUSTOMER, CUSTOMER_ADDRESS, CUSTOMER_PHONE
Two joins defined for the three tables:
CUSTOMER - CUSTOMER_ADDRESS (LEFT OUTER JOIN)
CUSTOMER - CUSTOMER_PHONE (LEFT OUTER JOIN)
Issues/Questions:
- The problem I have run into is that any query that uses Customer Id or Customer Name still causes a join to the CUSTOMER_ADDRESS and CUSTOMER_PHONE table even though I didn't use a field from those tables. I assume this is because OBIEE things that any query to that Logical Table using that LTS has to query it as the LTS is defined (so all three tables are joined in)
- Is there a way around this? If so, is it to specify separate LTS tables for the Logical Table Dim - Customer? If you do this, then there is no way to specify a LEFT OUTER JOIN and the query will just default to what is specified in the Physical Layer as an inner join.
- Curious as to what peoples thoughts are in general for how to decide whether to specifiy multiple sources in a single LTS or just add multiple sources to the Logical Table and the decision criteria for going either way.
Thanks in advance.
K
Edited by: user_K on Jun 3, 2010 11:09 AM
Edited by: user_K on Jun 3, 2010 11:10 AM

Answer 1

Thanks a lot for the example, that fixed the problem.
I've been reading the NSAPI programmers guide several times now and I was under the impression that you should either use <object> or <client>, never thought about this approach. Now when I re-read it is makes sense, but wasn't very clear at first.
I think I'll e-mail Sun to suggest an addition of the <Object> tag in their <Client> tag example (http://docs.sun.com/source/817-6252/npgobjcn.html#wp1045056) to make things a little more clear.
Thanks again, now I can finally implement the final configuration settings and plan for the actual switch later this evening.