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It’s almost that time again, and Rittman Mead will once again be attending and presenting at Oracle’s Open World conference and exhibition, running in San Francisco from September 19th-23rd 2010.

Our team are running thirteen sessions over the week, covering such topics as OBIEE 11g, Fusion Middleware 11g, Oracle Data Integrator, Oracle Golden Gate, Oracle Database 11gR2 and Oracle Exadata. Here’s the run-down on our sessions, and who’s presenting:

• Sunday 12.30pm, Moscone West 2002 : Mark Rittman, “Oracle Business Intelligence Enterprise Edition Dashboarding/Reporting and More”
• Sunday 12.30pm, Moscone West 2012 : Stewart Bryson, “Introduction to the ODTUG BI/DW Sunday Forum”
• Sunday 2pm, Moscone West 2020 : Jon Mead, “Oracle Exadata/Oracle Business Intelligence Enterprise Edition Retail Case Study”
• Sunday 4.30pm, Moscone West 2012 : Mark Rittman, Jon Mead, “Oracle Business Intelligence Enterprise Edition Panel”
• Tuesday, 3.30pm, Moscone West 3016 : Jon Mead, “An Oracle Exadata Case Study in the Retail Sector”
• Tuesday, 3.30pm, Moscone West 3020 : Borkur Steingrimsson, “Oracle GoldenGate In-Depth : What’s All the Fuss About?”
• Tuesday, 5pm, Moscone South 308 : Peter Scott, “Implementing a Retail Data Warehouse on the Oracle Exadata Platform : Lessons Learnt”
• Wednesday 10am, Moscone West 3010 : Mark Rittman, “Oracle Business Intelligence Enterprise Edition Architecture Best Practices”
• Thursday 9am, Moscone South 300 : Stewart Bryson, “Resuming, Restarting, Restoring : Three R’s of Data Warehouse Fault Tolerance”
• Thursday 11am, Hotel Nikko/Bay View : Stewart Bryson, “Real-Time Data Warehousing with Oracle BI and Oracle Database”
• Thursday, 12pm, Moscone West 3010 : Mark Rittman, “Oracle Business Intelligence Enterprise Edition Data Modeling Best Practices”
• Thursday 1.30pm, Moscone West 3010 : Venkat Janakiraman, “Oracle Business Intelligence Enterprise Edition / Oracle Fusion Middleware”
• Thursday 3pm, Moscone West 3020 : Venkat Janakiraman, “Oracle Data Integrator : ETL Loads on Oracle Essbase and Oracle Hyperion Planning”

We’ll also be at the various events, getting to as many sessions as possible and meeting up with our friends and customers within the industry. If you’re going to be there, stop by one of our sessions and say hello. We’ll also post the various presentations and papers on our website once the conference is over.

Vlamis Software Solutions, an Oracle Parner, along with NAVTEQ, are hosting a BIWA SIG (that would be the Business Intelligence, Warehousing and Analytics Special Interest Group) web seminar - BIWA SIG TechCast - Sept 8 - Noon Eastern (US) - Information Visualization Using Maps in Oracle Business Intelligence 11g. Use this link to register for the seminar.

There have been some changes happening on the Oracle Technology Network. As a result, the link to the Oracle BI EE 11g Certification Matrix that I had posted in an earlier post no longer works.
Use this link instead: System Requirements and Supported Platforms for Oracle Fusion Middleware 11gR1 (XLS format)
Bookmark this page for reference in either case: Oracle Fusion Middleware Supported System

This problem, which in essence is bad behaviour from Informatica bringing down Oracle, is a good illustration of unintended consequences of an apparently innocuous security setting. Per our company’s security standards, database passwords expire every 90 days. When this happens users are prompted to change their password before they can continue logging into Oracle. This [...]

I have a dilemma. In the BI system that I’m working on I have the perfect application for the use of Expression Filters. It is almost as if someone specifically devised this problem in order to tempt me into using them, and I really am very tempted indeed. Let me explain. In the application which [...]

In other parts of this series we have had a look at data warehousing books that cover the design and architecture of a business intelligence solution. I have also covered data warehousing books in the world of Oracle and data warehousing and business intelligence books for project management and business analysis. Today we’ll discuss data modeling books for building an Enterprise Data Warehouse

If you are involved in an enterprise data warehouse program (and by that I don’t mean Kimball’s conformed dimension stuff) you need to be familiar with all aspects of data modelling. This includes

- Requirements gathering
- Enterprise data modeling
- Conceptual/subject area modelling
- Logical modelling
- Physical modelling
- Dimensional modelling
- Normalization and denormalization
- Subtypes & supertypes
- Universal data modelling patterns
- Generic data modelling
- ER data modelling
- UML data modelling
- The collaboration process (bridging the business – IT divide)
- Selecting a data modeling tool

A well thought out enterprise data model is the foundation for a successful enterprise data warehouse.

I have put together a list of the most important data modelling books. These will teach you the tools and techniques of the best data modelers out there.

Data Modeler’s Workbench

Data Modeling Made Simple

Data Modelling Essentials

The Data Model Resource Book, Vol. 3

Mastering Data Warehouse Design: Relational and Dimensional Techniques

 Now that I have installed Oracle BI EE 11g, what I like to do is to create a another user with administrative privileges that I then use for my work. In this case, to satisfy a narcissistic urge I use my name as the user name - "abhinav".

To do that, I first need to login to the Administration Console of Oracle BI EE. which on my computer's installation is http://aagarwa-lap.idc.oracle.com:7001

So of course I have to let you know about a new video I'm in. But seriously, if you are in Sales, a seven minute investment of your time to watch two new BNET "At The Whiteboard" videos (I'm only in one of them) to learn more about implementing effective sales KPIs and improving CRM adoption among sales users will be well worth your time. Here you go.

 Document ID   Title   Doc Type   Modified Date  1077776.1 Bad Performance Starting BI Server o Presentation Server on Red Hat Enterprise Linux. PROBLEM 24-AUG-10 1163021.1 Why Biapps_odi Folder Missing In Bi Apps 7.9.5 Installation HOWTO 24-AUG-10 1186513.1 OBIEE 11g (OID) The Security Token cannot be authenticated PROBLEM 25-AUG-10 1145095.1 Installing Obiee 10.1.3.4.1 Using Weblogic 10.3.1, needs [...]

If you haven’t found them:

http://www.oracle.com/technetwork/middleware/bi-foundation/obiee-samples-167534.html

Till Next Time

It has been a while since I published Part 1 of the Essbase Studio Tutorial by Example. Finally a quick follow-up to the original that I promised I would get out - a  second part on adding drill-through capability - is available.  This document has been sitting around for a while.  I’ve been swamped and [...]

As mentioned in the blog entry here, BI Server 11g now supports more functions which were added to support the new UI features. Each of these functions can be used as part of the Logical SQL or can even be used directly in the Answers UI. In this blog entry we shall be looking at how some of these functions can be used.

1. SELECT_PHYSICAL: Though this is not a function, this is a new feature supported by BI Server that can bypass the BMM layer in the SQL queries. So, any SQL that uses SELECT_PHYSICAL will be more closer to the ANSI SQL standard. There are 2 main advantages of this

a. Any external reporting tools that generate SQL automatically can now leverage the functionality of BI Server. For example, in the blog entry here i had shown the difficulty in actually using Logical SQL with Cognos. But introduction of SELECT_PHYSICAL should alleviate this issue thereby making BI Server open for better integration externally.

b. Using SELECT_PHYSICAL one can now make direct joins across data sources without actually having the need to model them separately in the Business Model and Mapping layer.

With the addition of more in-memory operations in the BI Server, this should act as a point of integration for external tools that have the need to leverage the metadata framework of BI EE.

To illustrate how this works, lets look at the repository shown below,

As you see, the above repository contains all the relevant tables in the SH schema. Now, to use the SELECT_PHYSICAL command, lets go to the Issue SQL section of the BI EE and fire the SQL given below

SELECT_PHYSICAL
0 s_0,
CHANNEL_CLASS s_1,
SUM(AMOUNT_SOLD) s_2
FROM
"ORCL - SH".."SH"."CHANNELS"
A,
"ORCL - SH".."SH"."SALES" B
WHERE
A.CHANNEL_ID = B.CHANNEL_ID
GROUP BY CHANNEL_CLASS

Remember, though this is a SELECT_PHYSICAL SQL statement, BI Server will still do the parsing as the objects will have to reside inside the repository.

This option can be enabled at the ODBC/JDBC level as well. That way the DSN can be configured to just accept SELECT_PHYSICAL or SELECT commands.

I will cover more details of how this can be leveraged from external tools like QlikView, Cognos etc in a future blog entry.

2. AGGREGATE AT:

This function adds more multi-level analysis capabilities within the BI Server. This function provides the same functionality as the Level Based Measures. What this does is, it provides an ability to extract the values of a parent level in a query without having to SUM up the values in the lower level. To illustrate, lets look at the simple report below

Now, what we need is an ability to display the value of yearly sales alongside the quarterly sales. To do that, we need to enter the formula as shown below

AGGREGATE("Sales"."AMOUNT_SOLD" AT "Times"."TimesDim - Calendar Year"."Calendar Year")

If we look at the report now, we should see that we can compare the Yearly sales along the Quarterly sales i.e. the AGGREGATE AT function will not respect the filter on that dimension. If you want the filters to be honored as well then the older SUM BY functions can still be used.

If you look at the Physical SQL generated, you would actually notice 2 separate WITH clauses (minimum). One for the Sales figure. And the other for the Yearly Sales figure. The Yearly Sales figure will not have the filter applied.

WITH
SAWITH0 AS (select D1.c1 as c1,
     D1.c2 as c2,
     D1.c3 as c3,
     D1.c4 as c4,
     D1.c5 as c5
from
     (select sum(T44515.AMOUNT_SOLD) as c1,
               T44523.CALENDAR_QUARTER_DESC as c2,
               T44523.CALENDAR_QUARTER_ID as c3,
               T44523.CALENDAR_YEAR as c4,
               T44523.CALENDAR_YEAR_ID as c5,
               ROW_NUMBER() OVER
(PARTITION BY T44523.CALENDAR_QUARTER_ID
ORDER BY T44523.CALENDAR_QUARTER_ID ASC) as c6
          from
               TIMES T44523,
               SALES T44515
          where  ( T44515.TIME_ID = T44523.TIME_ID and
(T44523.CALENDAR_QUARTER_NUMBER in (1, 2)) )
          group by T44523.CALENDAR_QUARTER_DESC,
T44523.CALENDAR_QUARTER_ID, T44523.CALENDAR_YEAR,
T44523.CALENDAR_YEAR_ID
     ) D1
where  ( D1.c6 = 1 ) ),
SAWITH1 AS (select D1.c1 as c1,
     D1.c2 as c2,
     D1.c3 as c3
from
     (select sum(T44515.AMOUNT_SOLD) as c1,
               T44523.CALENDAR_YEAR as c2,
               T44523.CALENDAR_YEAR_ID as c3,
               ROW_NUMBER() OVER (PARTITION BY
T44523.CALENDAR_YEAR_ID ORDER BY T44523.CALENDAR_YEAR_ID ASC) as c4
          from
               TIMES T44523,
               SALES T44515
          where  ( T44515.TIME_ID = T44523.TIME_ID )
          group by T44523.CALENDAR_YEAR, T44523.CALENDAR_YEAR_ID
     ) D1
where  ( D1.c4 = 1 ) ),
SAWITH2 AS (select D1.c1 as c1,
     D1.c2 as c2,
     D1.c3 as c3,
     D1.c4 as c4,
     D1.c5 as c5,
     D1.c6 as c6
from
     (select 0 as c1,
               D1.c2 as c2,
               case  when D2.c2 is not null then D2.c2
when D1.c4 is not null then D1.c4 end  as c3,
               D1.c1 as c4,
               D2.c1 as c5,
               D1.c3 as c6,
               ROW_NUMBER() OVER (PARTITION BY D1.c2, D1.c3,
case  when D2.c2 is not null then D2.c2 when D1.c4 is not null
then D1.c4 end  ORDER BY D1.c2 ASC, D1.c3 ASC,
case  when D2.c2 is not null then D2.c2
when D1.c4 is not null then D1.c4 end  ASC) as c7
          from
               SAWITH0 D1 left outer join SAWITH1 D2 On D1.c5 = D2.c3
     ) D1
where  ( D1.c7 = 1 ) )
select D1.c1 as c1,
     D1.c2 as c2,
     D1.c3 as c3,
     D1.c4 as c4,
     D1.c5 as c5
from
     SAWITH2 D1
order by c1, c3 NULLS FIRST, c2

3. CALCULATEDMEMBER:

This function is used to derive calculated members using members at any level of a hierarchy. In 10g, we can do this from a pivot table. In 11g, this function has been introduced at the BI Server level itself so that we can leverage these directly from the repository.

To illustrate this, consider the hierarchy shown below

In this hierarchy, we want to find out the difference between Steven King’s Salary and his 2 direct reportees (Neena Kochhar and Lex De Haan). To do this, we need to use a function given below

CALCULATEDMEMBER("HR"."Employee"."EmployeeDim",'Test', MEMBER(100) - MEMBER(101) -MEMBER(102))

This would push the function directly on the parent-child hierarchy and give us the correct values. This function cannot be used if there are other attributes of the same dimension in the report. This is generally used by external application tools. But within BI EE Answers, there is no need for using this as we can achieve the same using Custom Groups and Calculations.

4. EVALUATE_ANALYTIC:

This is another significant new feature that can be useful to push down the oracle database analytic functions. I have covered EVALUATE number of times before for function shipping database functions. EVALUATE_ANALYTIC extends that further and provides us an ability to function ship the analytic functions as well. The syntax of this function remains the same. I will cover this in detail in another blog post as there are quite a few use cases where EVALUATE_ANALYTIC can prove to be very useful.

5. HIERARCHICAL FUNCTIONS:

BI Server now supports hierarchical functions like ISCHILD, ISROOT, ISANCESTOR, ISDESCENDANT & ISLEAF that can be used to traverse a Parent-Child hierarchy. These functions generally return a boolean data type (true/false) and hence can be used in filters to restrict data. They can also be used in column formula case statements.

For example, in a hierarchy if we want to know whether a specific member is a leaf node or not, we can use the below function to display Yes/No as an attribute of the parent-child hierarchy

CASE WHEN ISLEAF(Employee.EmployeeDim) THEN 'Yes' ELSE 'No' END

Next up is some interesting posts on the BI EE integration with Fusion Middleware & Essbase. I will be doing these posts towards the end of next week.

If you need to have windows recognize an increase in disk space, especially when using a Windows guest as a VMWare image this article is for you.

In a standard OBIEE implementation, we generally want to purge and re-build the cache after every ETL run. This post deals with how to programmatically purge and re-build cache and also schedule it.

Purging Cache
OBIEE provides ODBC-extension functions that can be used to purge cache programmatically. These functions can be called using NQCMD commandline tool. There are four different functions that can be used to purge cache.

• SAPurgeAllCache - Purges all cache
• SAPurgeCacheByDatabase - Purges all cache for a specific physical database
• SAPurgeCacheByTable - Purges cache for a specific physical table
• SAPurgeCacheByQuery - Purges cache for a specific query

Here's how to use the command in windows environment.

Create a text file using notepad with name "PurgeCache.txt" and add following line to it. Save the file to local disk (Let's assume to drive C:\)

Call SAPurgeAllCache();

Start command prompt and run following command. Note, there are four parameters in the command. You must replace this with values relavent to your implementation.

-d = ODBC datasource name
-u = Admin user name
-p = Admin Password
-s = sql file

NQCMD -d AnalyticsWeb -u Administrator -p Administrator -s C:\PurgeCache.txt

Since we used SAPurgeAllCache function, it will clear all cache on the data source . Refer this link for syntax of other functions.

Re-building Cache
Once the cache is purged, you may want to re-build cache for some of the frequently used reports to avoid delay in response to the users. Re-Building cache requires executing the "logical" SQL query against the data source. We can use NQCMD same way we used for purging cache. Instead of purge function, we have to include logical SQL statements in the text file.

Create a text file using notepad with name "BuildCache.txt" and add logical SQL commands to it. You can include more than one command separated by semicolon(;). Save the file to local disk (Let's assume to drive C:\). Below is example of the text file content.

SELECT Product."Department" saw_0, Product."Style" saw_1, Sales."SalesAmt" saw_2 FROM MYCATALOG ORDER BY saw_0, saw_1;

SELECT Product."Department" saw_0, Product."Style" saw_1, Sales."CostAmt" saw_2 FROM MYCATALOG ORDER BY saw_0, saw_1;

Start command prompt and execute the command same way we did for purging the cache.

NQCMD -d AnalyticsWeb -u Administrator -p Administrator -s C:\BuildCache.txt

Scheduling Purge and Re-build
You may not want to run purge/rebuild cache manually after each ETL run, so you can create a batch file using notepad, "Caching.bat" and add the two command that we ran manually to it. Save the file.

NQCMD -d AnalyticsWeb -u Administrator -p Administrator -s C:\PurgeCache.txt
NQCMD -d AnalyticsWeb -u Administrator -p Administrator -s C:\BuildCache.txt

We can schedule this file to run automatically using windows scheduling using following steps.

Go to Control Panel and double click "Schduled Tasks"

In the Schduled Tasks window, double click "Add Scheduled Task".

The Scheduled Task Wizard screen appears.
Click Next to continue.

Click Browse button on next screen. Navigate to the C:\Caching.bat and click Open button.
Next, you give the task a name and choose when to run the task.

Name the scheduled task.
Pick a name that will make sense to you later when you want to check the list or make any changes.

Choose when to run the scheduled task.
There are a number of choices as to when you would like to run the task:

Daily – once a day
Weekly – once a week
Monthly – once a month
One time only
When computer starts
When I log in

Click "Next" to continue.
Specify the day and time to run the scheduled task.

Click "Next" to continue once you have made your time selections.
Enter the name and password of the user who is authorized to run the task. Generally Administrator.

Click Next to continue.

Click Finish to complete scheduling the task.

As Mark had pointed out earlier here, one of the significant changes in the BI EE 11g release is the migration of security from the BI EE repository to Weblogic. Users and Groups will no more be maintained within the rpd. Even in an external authentication like LDAP, Groups will not be maintained within the repository. This is good in many ways as it can significantly reduce the size of the repository. The downside though is, in offline mode unless there is a change in any security object (like custom filters to a group etc), the users & groups will not become visible. The use of Web Catalog Groups is no more recommended. It still exists primarily for supporting upgrades. In this blog post, lets see how the new weblogic based security works.

There is a terminology change that we need to get used to while moving to BI EE 11g. Groups now refer to Weblogic groups. BI EE specific groups are called as Application Roles. The figure shown below explains the relationship between Users, Groups & Application Roles.

Weblogic security is much more comprehensive and it can support multiple external directories like LDAP, OID etc. It also supports table authentication. So, if you are planning on setting up external authentication, its preferred to set it up at the Weblogic layer. We can also setup external directories within BI EE (like in 10g).

To start with lets create a simple user bieeuser1 in the Weblogic Console Security Realm (http://localhost:7001/console).

While creating a user we can assign it to a provider. A provider is the authentication directory against which users will be authenticated. In our case, we have created the user in the default weblogic directory. In the same way lets create 2 more users bieerpdadmin & bieewebcatadmin.

The idea is to provide the following privileges to each of the users that we have created

bieeuser1 – Casual user with no access to the repository but with read only access to dashboards (no answers)
bieerpdadmin – Repository Administrator with full control of the Repository objects but with no control on the web catalog.
bieewebcatadmin – Web Catalog Administrator with full control on the web catalog but with no access to the repository

Remember, its not always necessary to assign users to weblogic groups. Users can be directly assigned to application roles. Once the users are created, lets login to the Weblogic enterprise manager and navigate to the coreapplication under the Business Intelligence folder.

Now, right click on the coreapplication and choose the Security->Application Roles option

This should list all the default application roles available within BI EE.

Let’s neglect the existing roles(ideally we will be reusing/reassigning the default roles as much as possible) and create 3 new roles.

1. BIEERoleUser
2. BIEERoleRPDAdmin
3. BIEERoleWebCatAdmin

For now lets not add any users/roles to these roles.

Lets now navigate to the Application Policies and start granting specific rights/grants to the roles that we created. Remember in any ADF application we need to define application policies so that they can be granted to individual users. We start with assigning the following privileges to the BIEERoleUser

1. resourceType=oracle.bi.server.permission,resourceName=oracle.bi.server.queryUserPopulation

This basically provides an ability to query the BI Server repository.

Lets assign this privilege to the BIEERoleUser application role.

In the same way lets assign the following privileges to the BIEERoleRPDAdmin and BIEERoleWebCatAdmin

For BIEERoleRPDAdmin

1. resourceType=oracle.bi.server.permission,resourceName=oracle.bi.server.ManageRepositories

For BIEERoleWebCatAdmin

1. resourceType=oracle.bi.server.permission,resourceName=oracle.bi.server.queryUserPopulation

Now that the roles have the right privileges, lets go back to the Application Role screen and start assigning the 3 users to each of these roles.

After assigning these, if you try to login to the repository in online mode, only the user bieerpdadmin can login. We have satisfied one requirement, that is we have created a user who is the repository admin. For presentation services, by default during install the privileges in presentation services get assigned to only 3 default groups BIAdministrator, BIAuthor and BIConsumer. So, to make bieewebcatadmin a true webcatalog administrator we have to go to the Application Roles and add the BIAuthor & BIAdministrator role to BIEERoleWebCatAdmin

This will automatically make the user bieewebcatadmin user to be the administrator of the webcatalog. Initially it is mandatory to assign a new role to the BIAdministrator role as that is pre-configured to be the only role having access to Privileges in Presentation Services. Granting BIAdministrator to a role also opens up the access to the repository. This can be disabled as well. It is not necessary to always create new roles and assign policies to them. Existing roles can be re-used and re-assigned. The entire security model is now more aligned with Oracle Platform Security framework so that all the fusion applications can integrate with each other seamlessly.

Are you are looking to get some hands on experience with OBIEE11g? Then join us for a free, interactive workshop where you will get hands-on experience in building ad-hoc reports, dashboards, and alerts using the latest version of Oracle Business Intelligence Enterprise Edition (OBIEE). Workshops will be available in the following cities.

Phoenix, AZ 85016 - Tuesday, August 31, 2010

Irvine, CA 92614 - Wednesday, September 1, 2010

El Segundo, CA 90245 - Thursday, September 2, 2010

San Diego, CA 92130 - Thursday, September 16, 2010

Each workshop is limited to 20 participants, so you should register soon, as they are filling up fast.

Here's the link to register: http://www.oracle.com/dm/11q1field/54690_obiee_workshop_series.html and here's the workshop agenda.

Last weekend I was surprised to see someone’s comment on the Oracle BI Forum on OTN. The fact that someone posted the question in the first place had surprised  me already. But the response to one of the top contributors of this forum is definitely a sign of disrespect. On top top of that, it was [...]

When you log into the sample dashboard of the latest Oracle BI release you are presented with the following:   When you click on the link; http://www.oracle.com/technology/products/bi/business-intelligence-foundation.html, you get redirected to; http://www.oracle.com/technetwork/indexes/products/index.html. Thanks to OTN I was able to find out that the actual link should be; http://www.oracle.com/technetwork/middleware/bi-foundation/obiee-samples-167534.html. Have fun. Tagged: 11g, obiee11g, SampleApp

A very short blog post to break the drought, but I didn’t hit any google results for this error so thought it might be useful to record it. In BI Publisher 10.1.3.4, trying to install the Scheduler (Quartz) schema, I got this error: Schema installation failed while creating tables. Schema may already exist. Please remove [...]

One of the important points to consider when moving from BI EE 10g to 11g is in understanding the BI Server behavior changes. Though there are quite a lot of changes in the underlying code for performance improvement etc, introduction of new features in 11g can potentially alter your generated queries in 11g. In this blog entry i will basically cover 2 main important changes that have been introduced in 11g. There are more actually, but that is something we will try to cover in our training days event.

1. Level Based Measures at Detail Level:

One significant change in 11g is the handling of level based measures at the detail level. For example, lets consider a measure AMOUNT_SOLD that is assigned to the detail day level of the date dimension.

In 10g, whenever we bring this column for reporting, we would basically see something as shown below i.e. the level will always be enforced.

In the case of 11g, there are 2 types of behavior

a. If the report contains normal attribute columns and when the query is at a grain higher than the measure grain (say the report is at the Year level), then normal aggregation will be applied and the level will not be enforced like in 10g. An example screenshot is given below

b. If the report contains hierarchical columns, then if the query is at higher grain than the measure, the measure values will become null. The values will appear at that grain or below. An example screenshot is given below

2. Priority Groups & Order of LTS:

In 11g, there is a new concept called Priority Groups. In 10g, the LTS that determines the final query is dependent on the ordering of the LTS in the dimension logical table(in most cases – but there are cases where we cannot be always be sure to guarantee this behavior). But in 11g, this is determined by the priority order set in each and every LTS.

For example, lets consider a case where there are 2 aliases for the same dimension CHANNELS as shown below

In the business model and mapping layer, lets assume that both the LTS are mapped to all the columns. Both the LTS are at the same detail level. Now, lets assign a priority group of 0 for the Channel Alias – B LTS and a priority group of 1 for the Channel Alias – A LTS. Also the SALES LTS of the Fact table will also be assigned to the priority group 0. In 11g, the LTS with the least number is considered as the one that has to be chosen for querying (highest priority)

Now, lets create a report containing columns from Channels dimension and the Sales fact.

If you look at the query of the report, you will notice that Channels Alias – B will be chosen as it is the one having the highest priority.

Lets now go back to the repository and reassign the highest the priority to Channels Alias – A as shown below

For the same report, if you look at the query now, you will notice that Channels Alias – A will be chosen instead of the B alias.