Interview Questions

What is Sort order columns?

We can sort the columns at 2 levels

1. Repository:At the presentation layer,sort the one column values based on another column

2. Answers:At the criteria tab->columns->sort the column values either ascending or descending order based on the requirement.

Can we handle the nulls?

Yes,we can handle either in repository and answers.

ifnull(column_name,0)->at expression of the measure column

What is the use of connection pool?

We can create different no.of connection pools in the project. It has the database connection details, no.of minimum users can access the application.

What is the difference between OCI and ODBC?

OCI will be specific to the oracle database but the ODBC connection, we can use with any datasource.

What is a table alias in obiee? and where and how will you create it.

Table alias can be created by right clicking the table in the physical layer then click alias. Table alias is mostly used for creating self joins.

Have you created Hierarchy in OBIEE. if so where and how?

Yes we can create hierarchy in BMM Layer of OBIEE in dimensions for the dimension tables. this can be done by right clicking the dimension table and click create dimension and then we should manually define the hierarchy and its levels.

What is Label-based measure ?

Level-base measure means, having a measure pinned at a certain level of the dimension. Monthly Total Sales or Quarterly Sales are the examples.
To create a level based measure, create a new logical column based on the original measure (like Sales in the example above). Drag and drop the new logical column to the appropriate level in the Dimension hierarchy (in the above example you will drag and drop it to Month in Time Dimension).

What is a bridge table ?

If you want to connect two tables where there is no relation ship you can use a third bridge table for connecting them which will have common columns in both tables, this is used in BMM Layer.

Can you change the location of the OBIEE Repository?

No, Not in Standalone OBIEE Install. You can give shared location in NQSCluster.ini if the OBIEE is clustered.

How many BI Services Node can be clustered together?

Answer :- 16

Can you run multiple rpd’s in a Single OBIEE Instance?

No. You should create another instance in the same server , then its possible.

What is SCD type 1 and 2.

SCD is slow changing dimensions. In type 1, we replace the changed dimension with old dimension. In type 2, we use surrogate keys and keep both the records(rows). Advantage of SCD2 is we keep history of the old dimension.

What are the Major Challenges You Faced While Creating the RPD??????

Every now and then there are problems with the database connections but the problem while creating the repository RPD files comes with complex schemas made on OLTP systems consisting of lot of joins and checking the results. Th type of join made need to be checked. By default it is inner join but sometimes the requirement demands other types of joins. There are lot of problems with the date formats also.

How Online/Offline mode impact Development and Delpoyment????

Online Mode- You can make changes in the RPD file and push in changes which will be immediately visible to the users who are already connected. This feature we may use in production environment.

Offline mode- can be useful in test or development environment.

What is Guided Navigation?

Guided navigation is a feature of Oracle BI Interactive Dashboards that enables the content and layout of Oracle BI Interactive Dashboard to change dynamically based on changes in the information being analyzed.

Specifically, sections in a dashboard page can be set up and only appear when there is “interesting” information in the data.

What is logging level?Where can you set logging levels?

You can enable logging level for individual users; you cannot configure a logging level for a group. Set the logging level based on the amount of logging you want to do. In normal operations, logging is generally disabled (the logging level is set to 0). If you decide to enable logging, choose a logging level of 1 or 2. 

What is the difference between Data Level Security and Object Level Security?
Data level security controls the type and amount of data that you can see in a reports. Object level security provides security for objects stored in the obiee web catalog, like dashboards,dashboards pages,folder,and reports.

Can you bypass siebel analytics server security ?if so how?
Yes. You can by-pass by setting authententication type in NQSCONFIG file in the security section as: authentication_type=bypass_nqs.instanceconfig.xml and nqsconfig.ini are the 2 places.

Where can you add new groups and set permissions?
you can add groups by going to manage>security>add new groups> You can give permissions to a group for query limitation and filter conditions.

What are the things you can do in the BMM layer?

Aggrigation navigation,level base matrics,time series wizard,create new logical column,comlex join.

Can multiple repositories run on the OBI Server?

Yes. OBI 11g using the Fusion Middleware technology allows for multiple instances a core application to run from the same physical server.

Where is the NQSConfig.ini now located?
INSTALL_HOME/instances/instance1/config/OracleBIServerComponent/coreapplication_obis1.

What is the RCU?
The Repository Creation Utility is part of the Oracle Fusion Middleware suite that provides a contained means of creating a database repository via a graphical user interface (GUI) installation wizard.

What is a KPI?
A Key Performance Indicator (KPI) is a core metric providing an instant glance of a business perspective usually displayed in a visually engaging way.

What is Scorecarding?
Scorecarding is a methodology that communicates the strategic goals to your organization and monitors their progress. A scorecard answers questions such as: Where is the organization going? How will w get there? What are critical success factors? How is the business doing against goals?

Are the write back features enhanced in 11G?
There are few enhancements on write back. The best enhancement is using the Action Framework which allows you to use prompts, etc. to enter data for write back, not just in a grid.

How do selection steps differ from filters?
Filters and selection steps are applied on a column-level basis and provide two methods for limiting the data in an analysis. A filter is always applied to a column before any selection steps are applied. Steps are applied in their specified order. Filters and selection steps differ in various ways. Filters can be applied directly to attribute columns and measure columns. Selection steps are applied after the query is aggregated and affect only the members displayed, not the resulting aggregate values.

How to startup OBIEE in Linux?

To start ....
./run-sa.sh start #starts obi server
./run-saw.sh start #start saw server
./run-sch.sh start #start scheduler

To Stop ....

./run-sa.sh stop #stop obi server
./run-saw.sh stop #stop saw server
./run-sch.sh stop #stop scheduler

What are Global Filter and how they differ From Column Filter?

Column filter- Simply a filter applied on a column which we can use to restrict our column values while pulling the data or in charts to see the related content.

Global filter- This filter will have impact on across the application.

How to Enable Drills in a Given Column Data?

Answer:- To enable Drill down for a column, it should be included in the hierarchy in OBIEE.

OBIEE 11G New Features (Reports&Dashboards)

1. REQUESTS are renamed as ANALYSIS. 2. IBOTS are renamed as AGENTS. 3. CHARTS are renamed as GRAPHS. 4. Map view is instroduced. 5. Presentation variables can hold multiple values. 6. KPI's and SCORECARD's are introduced. 7. ACTION LINKS, MASTER-DETAIL reports, SELECTION STEPS are introduced. 8. Selection and Groups are introduced. 9. Interaction tab is introduced. 10. Breadcrumbs have been added to help users understand their current location within Oracle BI content. 11. Ability to export an entire dashboard or a single dashboard page to Microsoft Excel 2007+ 12. Slider Dashboard Prompts. 13. Trellis Chart Creation 14. Waterfall Chart 15. Column Format --> Contains HTML markup 16. Selection Steps View

OBIEE 11G New Features (RPD)

1. Hierarchy object introduced in Presentation layer . 2. Join is done from FACT to DIMENSION. 3. 11g displays COLUMN NAMEs along with table names in mappings. 4. New time series functions PERIOD ROLLING and AGGREGATE AT is instroduced. 5. AGGREGATE PERSISTENCE WIZARD creates indexes automatically. 6. PARENT CHILD, UNBALANCED (RAGGED,SKIPPED) HIERARCHY are instroduced. 7. Repository has password. 8. Dedicated connection pool need for initialization blocks in 11g. In 10g, we can use any connection pool. 9. Now Repository version will be automatically maintains. 10. You can now generate an XML patch file that contains only the changes made to a repository. 11. LTS priority ordering. 12. ID columns for Descriptive Columns. 13. Lookup Logical Tables. OBIEE 11G New Features (Security) 1. USERS and GROUPS are created in EM. 2. Groups no longer exist and are replaced by Application roles. Data level security is implemented by using Application roles to which users belong to. 3. In Presentaion Catalog, AuthenticatedUser role is used instead of Everyone group. 4. Application roles are managed in an external policy store. Application role objects exist in the repository, but these objects are pointers (references) to the externally managed roles. 5. Users are managed in an external authentication provider and are no longer managed in the repository. User objects exist in the repository, but these objects are pointers (references) to the externally managed users. 6. In 11g any named user can be granted administrative permissions if desired. This compares to 10g where there was a single user with administrative permissions who was named Administrator.

OBIEE 11G New Features (Installation)

1. Repository Creation Utility(RCU) is used for creating repository. 2. Oracle WebLogic Server replaces Oracle Application Server and Oracle Containers for Java (OC4J). 3. Supports IBM WebSphere (11.1.1.7) 4. Many configuration settings can be done using EM. 5. BI Composer is automatically installed and configured 6. Oracle Business Intelligence 11g Installer includes ONLINE HELP for each installation screen. 7. Oracle Business Intelligence Uses New Command Line Utilities(WLST, OPMN) What is the benefits of data warehouse? A data warehouse helps to integrate data (see Data integration) and store them historically so that we can analyze different aspects of business including, performance analysis, trend, prediction etc. over a given time frame and use the result of our analysis to improve the efficiency of business processes. Why Data Warehouse is used? For a long time in the past and also even today, Data warehouses are built to facilitate reporting on different key business processes of an organization, known as KPI. Data warehouses also help to integrate data from different sources and show a single-point-of-truth values about the business measures. Data warehouse can be further used for data mining which helps trend prediction, forecasts, pattern recognition etc. Check this article to know more about data mining What is the difference between OLTP and OLAP? OLTP is the transaction system that collects business data. Whereas OLAP is the reporting and analysis system on that data. OLTP systems are optimized for INSERT, UPDATE operations and therefore highly normalized. On the other hand, OLAP systems are deliberately denormalized for fast data retrieval through SELECT operations. What is data mart? Data marts are generally designed for a single subject area. An organization may have data pertaining to different departments like Finance, HR, Marketting etc. stored in data warehouse and each department may have separate data marts. These data marts can be built on top of the data warehouse. What is ER model? ER model or entity-relationship model is a particular methodology of data modeling wherein the goal of modeling is to normalize the data by reducing redundancy. This is different than dimensional modeling where the main goal is to improve the data retrieval mechanism. What is dimensional modeling? Dimensional model consists of dimension and fact tables. Fact tables store different transactional measurements and the foreign keys from dimension tables that qualifies the data. The goal of Dimensional model is not to achive high degree of normalization but to facilitate easy and faster data retrieval. Ralph Kimball is one of the strongest proponents of this very popular data modeling technique which is often used in many enterprise level data warehouses. If you want to read a quick and simple guide on dimensional modeling, please check our Guide to dimensional modeling. What is dimension? A dimension is something that qualifies a quantity (measure). For an example, consider this: If I just say… “20kg”, it does not mean anything. But if I say, "20kg of Rice (Product) is sold to Ramesh (customer) on 5th April (date)", then that gives a meaningful sense. These product, customer and dates are some dimension that qualified the measure - 20kg. Dimensions are mutually independent. Technically speaking, a dimension is a data element that categorizes each item in a data set into non-overlapping regions. What is Fact? A fact is something that is quantifiable (Or measurable). Facts are typically (but not always) numerical values that can be aggregated. What are additive, semi-additive and non-additive measures? Non-additive Measures Non-additive measures are those which can not be used inside any numeric aggregation function (e.g. SUM(), AVG() etc.). One example of non-additive fact is any kind of ratio or percentage. Example, 5% profit margin, revenue to asset ratio etc. A non-numerical data can also be a non-additive measure when that data is stored in fact tables, e.g. some kind of varchar flags in the fact table. Semi Additive Measures Semi-additive measures are those where only a subset of aggregation function can be applied. Let’s say account balance. A sum() function on balance does not give a useful result but max() or min() balance might be useful. Consider price rate or currency rate. Sum is meaningless on rate; however, average function might be useful. Additive Measures Additive measures can be used with any aggregation function like Sum(), Avg() etc. Example is Sales Quantity etc. What is Star-schema? This schema is used in data warehouse models where one centralized fact table references number of dimension tables so as the keys (primary key) from all the dimension tables flow into the fact table (as foreign key) where measures are stored. This entity-relationship diagram looks like a star, hence the name.