I saw a post on the Oracle BI EE Forums today; Sorting month name. There were various solutions to the question. I think Kishore Guggilla came up with the best solution, so he deserves all the credits.
Although, it’s a very easy solution to a very simple ‘problem’, I thought I write a little post about the subject, because the solution can be used very often. Not only in a month sort.
Picture the following. I have created a dimension table with month names and month numbers.
Based on this dimension table I have created the following Business Model.
Now we can create a simple report with the month names.
As you can see the month names ar sorted alphabetically. We can verify that by the query fired.
If we want to sort the month names based on theire month number, we have various options. As said before I like the solution via the repository. In the repository you can sort a column, using another column. Just change the properties of the logical column. Now the BI Server knows that it hast to sort the month name via the month number.
Now we can create the same simple report with the month names.
As you can see now the month names ar sorted by month number. We can verify that by the query fired.
When you filter an a non-conforming dimension, you could get a null value for the fact which has all the dimensions as conforming.
Is this not exactly how the Oracle BI-server works? We have created one logical fact table and two different logical table sources (LTS). The Oracle BI-server creates seperate queries for each LTS in a Oracle BI Answers query.
Query I connects fact table 1 to all the dimensions, including a filter on the non-conforming dimension.
Query II connects fact table 2 one to the conforming dimensions only. Because there is no physical relationship between fact table 2 and the non-conforming dimension, it is not possible to filter query II on dtnc1.value3 = ‘3CCC3’ as well.
The results of both queries:
Lucky enough for me Nicolas did some investigating himself to:
Although published about 7 years ago, this subject still seems a source of questions. To understand the concepts of Oracle BI (OBIEE) better, it is good to check out the following blogposts as well. They will link to other blogs “Don’t forget the Logical Layer” & “Going to the core of Oracle Analytics” and will help you better understand the basis of OBIEE. This basis is an absolute must to get the most out of OBIEE.
There are some questions, which are popping up at the Oracle BI EE Forums regularly. One of those questions is;
*** How to model multiple facts against (non-) conforming dimensions?
I will try to work things out. Click on the images to see more detail.
Note: I am aware of the extra white space between the images. That’s not intended functionality, but lack of knowledge of WordPress.
Picture the following:
There are two fact tables and three dimension tables. FACT_TABLE_1 has two conformed dimension tables; DIM_TABLE_CONF_1 and DIM_TABLE_CONF_2 and one non-conformed dimension table DIM_TABLE_NON_CONF_1.
FACT_TABLE_2 has two conformed dimension tables; DIM_TABLE_CONF_1 and DIM_TABLE_CONF_2.
The Physical Model would have the following structure:
Based on the Physical Model we could construct the following Logical Model:
I have created one fact table which contains Logical Table Sources (LTS) for FACT_TABLE_1 and FACT_TABLE_2
As you can see I have created Dimensions (Hierarchy’s) for each Dimension Table.
FACT_TABLE_2 has no physical relationship with DIM_TABLE_NON_CONF_1. Therefore you should set the logical levels for FACT_TABLE_2 to the ‘Grand Total’-level of DIM_TABLE_NON_CONF_1. This way the Oracle BI Server won’t look for a join between DIM_TABLE_NON_CONF_1 and FACT_TABLE_2.
If you want to avoid nulls, set the detail levels for the facts. Set the ‘Grand Total’-levels for the metrics as well.
If we take a look at Oracle BI Answers, we can create a report which contains data from the following tables;
Now we can bring data from DIM_TABLE_NON_CONF_1 into this report. It is impossible to devide data from FACT_TABLE_2 over this dimension. Therefore the data will be the same for every value of this dimension.
It’s possible to report on facts and dimensions which not have a physical relationship to each other. Just make sure you create dimensions (hierarchy’s) for every dimension table. Next to that you should set the logical levels for your logical tables.