[Type the company name]

Application Life-cycle: SDLC(SOFTWARE DEVELOPMENT LIFE CYCLE)

            This is the End-to End process of an application in the organisation (From

requirements gathering to production support).

There are 4 phases in the life-cycle

1. Requirements Gathering

2. Development

3. Testing

4. Production or Support

1. Requirements Gathering

Business analyst(BA): He is the person or a mediator between the client and the

organisation.

First Business Analyst is going to interact with the client to know about the client

business and pain-areas, from that business analysis BA will prepare the

document called as Business requirement document or BRD or FSD(Functional

Specification document) or SPEC.

From the BRD,the development team will prepare the HLD and LLD.

HLD(High-level-document): Divide the BRD into different modules for requirement

analysis, prepared by developers.

LLD(Low-level-document): Gives the detailed information about each entity in the BRD

or HLD, prepared by developers.

GAP Analysis:This is the comparision between client requirement and reporting

tool features like is the tool fulfill all the requirements of the client or not.

POC(Proof of Concept):This is the dummy or a duplicate model where the

development team will cook the data manually and prepares a sample model

which is going to send for the client’s approval.

Note:The end product should be same with the POC.

2. Development 

There are 2 parts in development

ETL development: ETL developers will prepare a data-model with all dimensions

and facts.Also build an integrated dataware-house from the heterogeneous data

sources.

Reporting development:Once the DWH is built,the reporters will configure the

repository and generate the reports asa per the client’s requirement.

3. Testing

Tesing is the major part in any application or product development.There are 3 types of

testing in the OBIEE application development.

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Unit Testing:The developer will test the own stuff.

Peer-Reviews:Test the application within the organisation as the application

developed.

UAT(User Acceptance Test):This is a client test testing,the application will be

tested by some other company.

4. Production or Support

The company need to give the application support for one month by default.After that

based on the client’s decision, the development company or some other company will

give the production support.

Obiee interview questions and answers

1.Date format issue while export to excel format

A)Answers–>column propeties–>custom CSS style options(bottom of the window)–

>check the custom css style –>Give the following date format

—-mso-number-format:”mm\/dd\/yyyy\ hh\:mm\:ss AM\/PM” or ” mso-number-format:\

@”

Change the format based on you requirement.

2. When i logged into the analytics not able to see all the options available for

administrator?

A)First logged in as a administrator into Em, manage the privileges which is required for

the user

3.I want to display the 4 narrative views in a single compound layout,but first narrative

view width is 1000 and the other 3 views width should be 500.Is it possible?

A)No,With a single compound view we can’t achieve.

4.How can i sort values of column in subject area not in report ?

A)We can sort the column in 3 ways

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1.Ascending order

2.Descending order

3.Based on another column

In Rpd we can sort the column based on the another column

BMM layer—>properties of the column_sort–>General—>Sort order column —->select

the column_base(column_sort will be sorted based on the column_base).

4.Can we call multiple action from a single actionlink?

A)Yes,We can call the multiple action links from a single action link based on the

conditions.

5.What is the difference between joins in physical layer and BMM layer?

A)Both are same,but can give the complex conditions in BMM layer.The Query always

fire from physical layer only.

6.I have 2 tables in DataBase table1 and table2

a)Imported together with keys and foreign keys?

bJoins will be automatically established in the physical layer.

b)Imported together only with keys?

Ans:-Keys will remain but joins not

c)Dragged the 2 tables from physical layer to BMM layer(along with Joins),which act like

fact table and which act like dimension table?

Ans:-Primary key—–Dimension

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Foreign key——-Fact

d)Same as (c) but without Joins?

Ans:-Both act like fact tables in BMM layer

7.You recently changed the columns of your presentation catalog as your manager

wants to enforce naming standards for all customer facing applications. What happens

to all the dashboard requests written prior to this change?Do they function properly or

do they appear broken?”If yes, they will function”, How does they work?”If not,reports

appear broken”, what can you do to fix this?Give examples?

Ans:-If alias table is available for presentation table then all the reports work fine.

8. I have configured the repository(3 layers) and saved.I have generated some reports

and saved.If I change the presentation catalog name then it is showing that you don’t

have permissions to access this subject area in answers.How can you fix this?

Ans:-Goto Advanced tab(In answers) Change the subject area name and set XML it will

automatically display the subject area.

PERFORMANCE TUNNING FOR REPORTS AND DASHBOARDS

9.You come Morning to the office And all the users are complaining about the OBIEE

reporting system is very slow (dashboards). What is your approach to resolve the issue?

Ans:

1. First check NQServer.log

2. Admin Tool -> click Session Manager. Check if there is any bottleneck and

accordingly resolve.

Refresh the sessions………

3. Analytics or Answers -> Administration-> Manage Sessions

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Check the physical query and execute from the back-end(BE).

10.Performance Tuning at real time

A)Performance Tuning is the huge topic to answer;

let’s take step by step approach as follows…

Check whether the same query is running or anyone update the query.If the same query

is running then follow the steps given below,

When you open the dashboard page, first figure out whether Prompt or Report is taking

more time.

If it is prompt, check for any multi select prompts which are taking time to load all

values.. (best practice is set default values).

If Report is taking longer time, set some default filters and query for just couple of

records and check the report performance.

Take physical SQL from the session log (if SQL is not generated check for log level

whether it is less than 2).

Run this Physical SQL in the TOAD or any SQL Editor.

Check Explain plan for the cost of the query.

Hash Joins/Cartesian Joins are always kills performance.

Some-times, Force Inner-join also helps to force the tables to have inner-join between

two tables.

Check are there any “Full Table Scans” happening instead of Index Scan.

Consult your DBA for the Stats.

OBIEE PRESENTATION LAYER BEST PRACTISES

Presentation catalog should map to one Business model & mapping layer(BMM) layer

objects only.

Use parent folders and sub-folders to group facts and similar dimensions together.

Avoid the use of aliases when a new presentation column is created.

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The presentation columns in a table should be sorted alphabetically if no specific order

is asked by the customer.

Make proper use of the permissions in this layer like authentication and authorization.

Don’t use special symbols (“) in column name, though its permitted.

Presentation columns should not have the same name as presentation table.

Eliminate unneeded objects to reduce user confusion.

Limit number of objects in folder to 7-12 (for performance tuning only).

Use object description field to convey information to users when they hover the mouse

in answers on a presentation column.

Keep names short to have space on reports and give the meaningful table names and

columns names to identify easily on subject areas. Remove primary key columns and

other unnecessary columns that does not going to use in the creation of the reports.

Try to create separate folder for each data mart  (HR, operation, SCM, sales) if it is

coming from same logical layer.

Get costumer sign off of the presentation layer structure before building reports. This

will avoid later replacements of columns which affects the report.

BMM LAYER BEST PRACTISES

1. Always run Global Consistency Check before releasing a repository:

 Whenever we make changes to a repository, always be sure to run Global Consistency

Check. It is bad practice to release a repository that still contains consistency check

errors. In some cases, consistency errors prevent Oracle BI server from loading the

repository. Use the Consistency chec k manager to identify and debug check messages.

Note: Whenever you do Consistency check , Right Click the Changed Business Model

Object and go for Check consistency rather than using the Global Consistency Check.

This will minimize the time needed for Consistency Check.

2. Minimize the use of Snow-flakes. Always go for Star Schema’s:

Every logical fact table must join to atleast one logical dimension table.

Note that when the source is a fully de-normalized table or flat file, you must map its

physical fact columns to one or more logical fact tables, and its physical dimension

columns to logical dimension tables.

3. Create dimension hierarchies for every Dimension in the Business Model:

 Even if a meaningful hierarchy definition cannot be thought of, just create one with the

Grand Total Level and Detail Level. For Dimension Hierarchies the ‘Number of Elements

at this level’ should increase from 1 at grand Total to the corresponding distinct values

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at each level. This can be approximate values; need not be the exact ones. Define keys

at each level of the Hierarchy.

4. Don’t keep unwanted physical columns in the Logical Layer:

5. Give Meaning ful Names to the Logical columns. Avoid assigning a logical column the

same name as a logical table or Business Model Object:

6. Logical Fact & Dimension table columns:

Always assign a primary key for logical dimension tables. All logical dimension columns

should be renamed in a way that is meaningful to users.

Bring only required columns into BMM layer for reporting.

Do not assign logical primary key for logical fact columns.

Create “dummy” measures to group facts.

7. Use Multi User Development Environment:

Use the Multi-User Development facility if there are multiple developers. Multiple

developers to connect “online” to the same repository file and Making changes is not

recommended.

Multi User Development allows user to define a series of projects with in the repository

file, where each project is a subset of the entire repository. If developers want to make

changes, they can check out a project to a local machine make and test the changes,

and then check the modifications back into the master repository file.

8. Level-based Metrics:

When creating level-based measures, make sure that all appropriate fact sources map

to the appropriate level in the hierarchy using aggregation content. You set up

aggregation content in the levels tab of the Logical Column dialog for the measure. 

Note that this is different from the content tab of the Logical dialog for the measure.

Note that this is different from the content tab of the logical table source dialog, which

is used to specify the grain of the source tables to which it maps. You only need to set

up aggregation content in the levels tab of the logical column dialog for level-based

measures. For measures that are not level based, leave the logical level field bank.

9. Separate business model:

Even if you have only a single data source or schema in the physical layer, or you have

only one physical data source for the repository, it is still good practice to break out the

physical objects into multiple business models in the BMM layer to represent the

independent areas of functionality.

10. Arrange the logical columns alphabetically if customer does not require any. This

will save time when you revisit:

11. Fix the warnings if any, don’t ignore it:

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12. Performance Tuning:

 Minimize the use of conditional checks and ‘CASE WHEN’ usage in the formula of

Logical columns. This will affect performance. Instead make proper use of the where

clause content filter of the LTS if the condition applies to all the columns/ measures in

the logical table.

Make proper distinction between count and count distinct. If you are counting on a

unique value column don’t use count distinct. This will affect performance.

Avoid dimensions in Fact tables and avoid measures in dimension tables.

OBIEE INTERVIEW QUESTIONS

1.What you did in physical layer,BMM layer and Presentation layer?

Ans: Physical layer:Physical layer is a connection between database and repository

by using connection pool.We can import the data from the different data sources, no.of

connection pools, aliases like  tables and columns, duplicate tables, opaque views and

physical joins etc.

BMM layer:Also called as Logical layer, Actually we implemented the logic here.We

can do the calculations, create the logical tables and columns, establish the joins like

physical and logical or complex joins, dimensions, level-based-metrics etc.

Presentation layer:We can show only the content which we want to show the end-

user, We can implement authorization and authentication, Implicit fact column and sort

order column etc.

2.What are Level-Based-Metrics(LBM)?How you use in your project?

Ans: Level-based-metrics show the measures at different levels based on the

dimension hierarchy. Generally LBMs  will use to display the data at month, week and

day level. To show this we will create the alias measure columns. Explain more details

from your project.

3.What is Dimension Hierarchies?Explain the procedure to create the

Hierarchy? 

Ans: Below link give the complete procedure for creating the dimension hierarchy..

http://oracletechnotalk.blogspot.in/2012/04/creation-of-hierarchy-in-

obiee.html

4.What is Sort order columns?

Ans: We can sort the columns at 2 levels

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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.

5.Rate yourself in SQL?

Ans: Here you need answer very carefully because based on your rating they are ready

to fire the questions on SQL. You have the minimum knowledge in SQL like select

statement, joins, performance concepts etc.

6.What is Implicit fact table and Implicit fact column?

Ans: A common fact table for dimension tables is called as Implicit fact table. An

Implicit fact column is a column in a Implicit fact table, we can select the best path

between the dimensions. Implicit fact column is decided in presentation layer.

7.Can we handle the nulls?

Ans: Yes,we can handle either in repository and answers.

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

8.What is the use of connection pool?

Ans: 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.

9.What is security in OBIEE?

Ans: Security in OBIEE can be implemented in 2 ways.

1. Authentication:Verify and validate the users against the system. 

2. Authorization:Validate the users against the Data.

10.What is Authentication?How can we implement?

Ans: Verify and validate the users against the system.We can implement the

Authentication in 4 ways

1. External table

2. Operating system

3. Data base

4. LDAP

11.What is Authorization?How can we implement?

Ans: Validate the users against the Data. Data can be limited the users by

1. Object level

2. Data level

3. Reports/Dashboard level

Did u get the data from any other data sources? If yes how?

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Yes,ofcourse client will provide the data in different formats like excel sheets, files,

cubes etc. We can import the data by creating the drivers for data sources.

Can i import the data directly from other sources to repository?

yes, we can directly import the data to repository

How to set the logging level in repository?

manage->identity->goto the user->set the logging level

The logging level for developer:min 2

The logging level for Administrator:upto 7

In production phase the logging level should be disabled. We can set the logging level

for a specific request at answers

Have you ever worked with ETL-tools?

As a reporting developer, i know the flow of ETL process. I never worked on that.The ETL

people takecare of everything.

Which type of schema you are used in your project?

Actually most of the projects are designed like a star-schema.My project is also used

star-schema as a data model.

What is star and snow-flake schema?

For complete details about star and snow-flake schema

http://oracletechnotalk.wordpress.com/2012/04/10/basic-dataware-housing-

interview-questions/

What is fact and dimension table?

The detailed description of fact and dimension tables

http://oracletechnotalk.wordpress.com/2012/04/10/basic-dataware-housing-

interview-questions/

What is the flow of your porject?

Every project must follow the software development life cycle.

Generally,the porject flow may like requirements gathering, Development(ETL and

Report), testing and Production.The flow of project may differ from project to project

based on domain like retail, telecom, healthcare, construction etc.

The complete knowledge on SDLC

http://oracletechnotalk.wordpress.com/2012/04/22/obiee-application-development-

life-cycle/

What is Dataware housing?

http://oracletechnotalk.wordpress.com/2012/04/10/basic-dataware-housing-

interview-questions/

Rate yourself in SQL?

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OBIEE developer must have the knowledge on sql because he need to test his own

stuff.Minimum knowledge of SQL is required for dataware housing developers.The rating

should be dependent on the person knowledge.

Tell me About yourself?

This is the major interview question for freshers and experienced. Everyone should

prepare before going to the interview.

Experienced:Tell ur name with experience what you have with current and previous

organization and then explain the porject what you done. If they expecting more then

give your educational details but no need to mention the family back ground.

What are your roles and responsibilities in your current project?

As a OBIEE developer,the reponsibilities like repository configuration and reports

generation based on the client requirements. At the end we need to implement the

security.

From where you start your work in daily routine?

Daily i got a mail from my reporting manager with a attached document. It includes all

the requirements and details of the work. 

What is the architecture of OBIEE?

http://oracletechnotalk.wordpress.com/2012/04/15/obiee-architecture/

Explain the 3 layers of the repository?

http://oracletechnotalk.wordpress.com/2012/04/15/obiee-architecture/

What is connection pool and how many connection pools you have in your project?What

is the purpose?

Actually connection pool is a link between repository and database. For more details use

the link

http://oracletechnotalk.blogspot.in/search?q=connection+pool

We can use multiple connection pools for to increase the performance. The no.of

connection pools may dependent on the project. We created different connection pools

for

security implementation,users and variables creation etc.

What is the difference between Obiee 10g & 11g?

OBIEE 10g:

We have 2 joins, foreign key join and complex join.

We have only level-based hierarchy in the logical layer.

All the configuration settings will be done at NQSconfig file.

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OBIEE 11g:

we have only 1 join, new join.

We have different hierarchies; level-based hierarchies,parent-child hierarchies,ragged

hierarchies,skipped hierarchies.

All the configuration settings will be done at the enterprise manager.

we have option like look-up table.

In answers,the chart view renamed as graph.

which version of OBIEE you are using?

Go to help in the repository of your project. There we can get the exact version of

OBIEE.

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 data source.

Have you ever worked on Joins?If yes how?

Yes, In physical layer i worked on joins based on the data-modelling document.

DATAWAREHOUSE FUNDAMENTALS

Dataware house is a 

Non-volatile: Permanent data(stores historical data or past data)

Subject-oriented: Data will be stored according to the subjects(like data-marts)

Integrated:Make a single source from heterogeneous sources

Time-variant: Data changed over a period of time

Dataware Housing: It is process of storing and retrieving data from warehouse.

Steps Involved from database to datawarehouse:

1. Extract the data from the heterogeneous sources and load into staging area(Source

Dependent Loading)

2. Apply transformations on staging area and load into datawarehouse (Source

Independent Loading)

3. Generate the reports from the datawarehouse by using a reporting tools like OBIEE,

Cognos etc.

We can generate the reports from the OLTP or databases but the performance may

decrease because the no.of  joins are more.

why we do reporting?

Reporting is an essential event for analysis of  the data of the specific organisation.

Anyone can analyse like management, users, partners etc.We can forecast the values

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by using the reports or reporting tool. Reporting will be exist in all domains like Retail,

Tele-communication, Insurance, Banking, Education, Public sector industries or factories

and private sector industries.Analysis of data is everywhere like small-scale, medium-

scale and large-scale industries. 

PHYSICAL LAYER IN OBIEE

Physical Layer:The name itself is saying,it is having the direct relation between the

repository and database.This is the one o f the most important layer in the

repository.The query will be executed from the physical layer only.Joins in the other

layers should be same with the physical layer.We can’t rename the object names in the

physical layer.In this layer we can import the data,creating connection pools,alias

tables,duplicate tables,opaque views, keys and joins.

Data sources:We can Import the data from different Data sources like oracle, my-sql,

excel sheets, XML data and cubes(OLAP and ESS base) by using different drivers. Data

will be imported with key or without keys.

Connection pool:We can create a multiple connection pools for single repository to

increase the performance.These are used for accessing users,variables and

implementing the security etc.

Tables:Alias and duplicate tables will be created in the physical layer.

Alias table:It is copy of parent table and always functionally depending on the parent

table.Alias table will be created for re-use the same table for different purpose.

Duplicate table:It is a copy of parent table but don’t have the  relation,once created.

Keys:If u import the tables without keys,here we can create the keys based on the

data-modelling.The joins will be established in the physical layer only based on the

primary and foreign key relation.

Opaque views:Opaque view is physical select statement,which does not occupy any

space in the repository.We can deploy or un-deploy from repository to database.

PHYSICAL LAYER BEST PRACTISES

PHYSICAL LAYER

Don’t import foreign keys from the database.

Avoid circular joins by using alias tables.

Use a different connection pool for different data sources.

Use a different connection pool for variables,data sources and security configuration.

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Establish the joins in the physical layer based on the data-modelling or client

requirement.

Use the max no.of users for each connection pool.

Delete the unused physical objects from the layer by using Remove unused physical

object utility.

Update the row-count by using Update physical layer to check the database connection.

Avoid hints in the physical table level

Don’t establish join between fact and fact table

Avoid to create a view or physical select statement in the physical layer

Remove the unused connection pools,it might lead to BI server crash as it continuously

ping to the connection.

Better to disable the database features in the DB-features configuration file.

Always use a data-ware house or OLAP(online analytical processing) system as a

database for geenrating reports.

Use proper naming convention for physical table and alias table also.

Always define your catalog under projects.

Ensure to check “execute queries asynchronously” option in the connection pool details.

CONFIGARATION AND LOG FILES IN OBIEE

Configuration files:These are the default files for every tool, it will store the default

settings of the tool. We can change the settings based on the requirement.

Configuration files of OBIEE are

Configuration files of RPD:

NQSconfig.ini: We can configure the RPD into BI server, setting-up the cache

parameters, security by-passing, usage-tracking, setting up the time-zone, date, time-

format,language and buffer stack size properties.

DBfeatures.ini: We can enable/disable the database features.

NQSCluster.ini: Maintains the servers in the machine(When multiple servers existed

on the same machine).By default in disable mode.

Log files of RPD: Log files are Informative files of anything.

NQServer.log: It will give the information about the BI server like when server starts

and stops and why server is not started.

NQSQuery.log:Information about the query manger like how much time it will take to

execute the query and performance of the query.

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NQSAdministration.log:Information about the administration tool like problems with

administration tool and all.

NQS Scheduler.log:Information about the schedulers like administration tool and

analytics.

Configuation files of Analytics :

Instanceconfig.xml: It will store all the settings of presentation service or Analytics

like reports, dashboards and all the elements .

Web-catalog: Web catalog is a folder,it will store the all the settings of a

application.Maintains an individual  catalog for application is the best-practice for

deploying the application.

In OBIEE 11g,all the configuration settings will be done at enterprise manager.

Enterprise manager is a third-party server, here all the settings are manages like

configuration of RPD, cache management, users and groups, web catalog settings.

OBIEE ARCHITECTURE

(Oracle Business Intelligence Enterprise Edition) latest version is 11.1.1.5 or 6.It is a

reporting tool for generate the reports to analyse the data.OBIEE has 2 default servers

BI server and Presentation server.It has 6 components in the architecture

1.Presentation services(Answers or Analysis)

2.Presentation server

3. Repository

4. BI server

5. Database connection(ODBC (Open database connectivity) or OCI (Oracle call

Interface))

6. Enterprise Data ware House

Presentation Services:This is a front-end page for users or clients.User can see the

reports from the Answers or Analysis  page.It contains answers, dashboards, account

details privileges of the specific users.We can the reports and dashboards based on the

client requirement.By starting the presentation server,we can operate the presentation

services.

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Repository:It is also called as RPD or RCU.Metadata settings are configured in the rpd

level.It has 3 layers

Physical layer:It has the direct connection with the database.We can apply the joins

between fact tables and dimension tables based on the data-modelling.

Business model and mapping layer:The logical changes will be done here like creating

logical joins(complex joins),new columns or tables,hierarchies etc.

Presentation layer:The objects will be visible to the users what placed in

the presentation layer.We can apply the security setting in the presentation layer.

We can operate the Repository settings by starting the BI server.we can open the RPD

in either online or offline mode

Database connection:This is the database connection between database and

OBIEE.The database connection  is either ODBC or OCI.

Data-ware House: Data-ware House is a huge data storage space for retrieving data.

OBIEE architecture interview questions and answers

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What are the major components in the OBIEE architecture?

a. Client

b. Presentation services(along with cache)

c. Repository

d. Database connection

e. Enterprise datawarehouse

f. Scheduler(along with cache)

What are the different layers of OBIEE Repository?

a. Physical Layer

b. Business Model and Mapping Layer

c. Presentation Layer

What are the folders available in OBIEE?

Oracle BI(Administration)

Oracle BIdata(analytics)

What are the Key Configuration Files in OBIEE

NQSConfig.ini,

DBfeatures.ini,

NQSCluster.ini,

odbc.ini,

instanceconfig.xml

What are the different Log files in OBIEE?

NQServer.log

NQSQuery.log

NQSAdministration.log

NQS Scheduler.log

What are the minimum services needed to load a repository file onto memory and view

a dashboard which has reports that have been refreshed on a scheduled basis?

BI server (Administration Tool)

Presentation Server (Analytics or Answers)

Scheduler server (Scheduling the jobs)

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What is the location of the administration configuration files?

drive:\OBIEE 11g\instances\instance1\config\oracleBIservercomponent\

coreapplication_obis1\file name

What is the location of the repository?

drive:\OBIEE 11g\instances\instance1\bifoundation\oracleBIservercomponent\

coreapplication_obis1\repository

What is the location of the presentation services configuration files?

drive:\OBIEE 11g\instances\instance1\config\oracleBIpresentationservices

component\coreapplication_obis1\instanceconfig.xml

What is the location of the administration log files?

C:\OBIEE11g\instances\instance1\diagnostics\logs

OBIEE Interview Questions & Answers

1. Explain the Architecture of OBIEE and what each components do?

Answer :- OBIEE Consists of Presentation Services(Web),Oracle BI (Analytics Engine)

Server

The client (Answers) constructs sql and passes it to the Analytic Engine and then the

Oracle BI (Analytic Engine) parses the physical sql to the Datasources and retrieve the

data back to the Engine and presents to the presentation Services .

2. How to get sql from obiee for reports?

Answer :- There are many ways to get the sql

a. Modify the request and click Advanced in that you get xml code and also the actual

sql.

b. In the catalog Manager click Tools –>Create Report .In the Create Report Window –>

Click Request SQL and save the sql to the physical path in your PC.

c. Enable Loglevel to 2 in the OBIEE Admin Tool from Mange-> Security and enable the

log level to 2 by clicking properties for the user, then go to the NQQuery.log in

BI_HOME/OracleBI/Server/Logs.You will find the SQL for that User.

d. By clcking Administration->Manage sessions-> view sql.

3. How will you do sort in Reports in OBIEE Answers.

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Answer :- Click modify and then click sort (order by icon) on the relevant column in the

criteria pane.

4. How will you do different types of narrative Reports in OBIEE?

Answer:- By clicking modify request and Narrative View and by giving @1 for the first

column result and @2 for the 2nd column and son on and we can also give a heading for

No Results by clicking the Narrative view.

5. How will you create Interactive Dashboards ?

Answer:- By clicking Administration and Manage dashboards and by adding column

selector also by using view selector etc.and also by using prompts.

6. What is write-back in obiee ?

Answer:- In Reports of Answer you can give a column as updatebale and then view the

reports,this option is called write back.

7. How will you execute Direct SQL in OBIEE?

Answer:- By clicking Direct Database Request below the subject area in Answers.

8. How will you create report from two subject areas

Answer:- From the Criteria Pane of the Report Created from First Subject Area

come to the bottom of the page and click combine request. but the options are limited

for combining like union etc..

9. How will you Port changes for dashboards,reports,rpd from development to

production?

Answer:- For the RPD use the Merge option in Admin Tool and for dashboards and

reports use Content Accelerator Framework.

10. What are the different types of variables in OBIEE? explain

Answer:- There are two types of variables in obiee.

a.Repository variable.

This variable is for the whole repository.

b.session variable . session variable can be system variable and non system variable.

system variable uses NQ_SESSION. —- (system reserved variable). examples of non

system variables are user defined filters etc.

11. How will you enable or disable caching in the system level and table level?

Answer:- In the NQSConfig.ini file use ENABLE under CACHE Section for System Level

for tables .If you want to enable the cache at table level , open the repository in offline

mode(not the current working repository). this should be different from the current

repository and click enable or disable the cache . right click the table and properties and

click the cache or deselect the cache. then merge the repository with the current

working one.

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12. How will you go about adding additional column to the repository in the presentation

layer?

Answer :- Check whether the table is already existing if so add in physical layer ,then

BMM and then Presentation layer, then reload server metadata ,then it will be visible to

all users.

13. How will effect the changes for a report , if for certain users only the column

heading in the report should be changed?

Answer:- Using session variables for that user.

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

Answer:- 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.

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

Answer:- 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.

16. What is Level Based Metrics.How will you create it?

Answer:- Leval-base matrics 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.

17. What are the different layers of OBIEE Repository?

Answer:- Physical Layer, Business Model and Mapping Layer, and Presentation Layer.

18. What is Authentication? How many types of authentication.

Answer:- Authentication is the process by which a system verifies, through the use of a

user

a. Operaing system autentication

b. External table authentication

c. Database authentication

d. LDAP authentication

19. What are the different types of security you have worked in OBIEE?

Answer :- Object Level and data level.

20. What is a bridge table ?

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Answer:- If you want to connect two tables where there is no relation ship you can use a

thrid bridge table for connecting them which will have common columns in both tables,

this is used in BMM Layer.

21. You come Morning to the office. and all the users are complaining about the obiee

reporting system is very slow(dasboards). what is your approach to resolve the issue?

Answer:- Mainly check NQServer.log and in Admin Tool -> click Session Manager. check

if there is any bottleneck and accordingly resolve.

22. What are the different log files in OBIEE?

Answer:- Following are the different log files inOBIEE

NQServer.log , NQQuery.log, NQSAdminTool.log etc.

There are mainly 25 Configuration files available in obiee.

23. What are the Key Configuration Files in OBIEE?

Answer:- NQSConfig.ini, NQSCluster.ini, odbc.ini, instanceconfig.xml

24. How will change port of obiee answers?

Answer:- By changing its port in instanceconfig.xml

25. What is ClusterServices in OBIEE ? Why its used?

Answer:- To Scale up the Performance by clustering and distributing the services across

multiple Servers ClusterServices are used.

26. Can you change the location of the OBIEE Repository?

Answer:- No, Not in Standalone OBIEE Install. you can give shared location in

NQSCluster.ini if the OBIEE is clustered.

27. How many BI Services Node can be clustered together?

Answer :- 16

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

Answer :- No . you should create another instance in the same server , then its possible.

29. How will you implement security in obiee,so that subjects areas accessed by one

group are not accessed by another group.

Answer:- Using Security Manger in OBIEE Admin Tool, by creating two user groups and

allowing only part of the subject area for one group and other part to the other user

group.

30. What is SCD type 1 and 2.

Answer:- 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 dimensiont.

31. What is Star Schema and SnowFlake Schema?

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Answer:- Star is one fact and many dimensions where as Snowflake design is one fact

and many dim’s and dim’s can have additonal dim relations.

32. How to startup OBIEE in Linux?

Answer:-

./run-sa.sh start #starts obi server

./run-saw.sh start #start saw server

./run-sch.sh start #start scheduler

33. How you generally Approach to ur Analytics Project?

Answer:- Any project should start from defining the scope of the project and the

approach

should be not to deviate from the scope.

Then the project should be functionally divided into smaller modules generally done by

project managers along with technical and functional leads.

The functional leads then decide on majorly three things:

According to the defined scope of the project they start gathering requirements while

interacting with the clients.

They had a discussion with the technical leads and try to reach a solution.

Technical leads decides what schemas to create and what requirements are going to

fulfill by that schema.

Technical leads discuss all this with the developers and try to close requirements.

Simultaneously testing and deployment is planned in a phased manner.

34. How we are going to decide which schema we are going to implement in the data

warehouse?

Answer:- One way is what is mentioned in Question above.

If one ask you to blindly create schemas for the warehouse without knowing any

requirements,

You can simply first divide the schemas on the basis of functional areas of an

Organization which are similar to the modules in an ERP like sales, finance, purchase,

inventory, production, HR etc.

You have to broadly describe the expected analysis an organization would like to do in

every module. This way you would be able to complete at least 40-50 % of the

requirements. To move ahead, study the data and business and you can create few

more schemas.

35. What are the Challenges You Faced while making of Reports?

Answer:- Making of an report has never been a difficult task. But problem comes when

users are reluctant to adopt a new system. Many developers have experienced that if

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they are not able to create the report in exactly the way they used to see, they will keep

asking for the changes. Developers approach should be to first show them what they

want to see and then add more information in the report.

36. What you will do when your Report is not Fetching Right Data?

Answer:- This is the biggest problem in report creation and verification. There could be

two reasons for report not fetching the right data.

1. Mostly clients do not have correct data in their database and on top of that to correct

the results they make some changes at the report level to bring the desired result which

you may not e aware of while creating the reports. Clients try to match the data with

their existing reports and you never get the correct results. you try to discover the

things and at later stage come to know of all these problems and you are held

responsible for this delay. Hence always consult the SPOC(Single Point of Contact) and

try to understand the logic they have used to generate their reports.

2. If the database values are correct, there there could be a problem with the joins and

relations in the schema. You need to discover that analyzing and digging deep into the

matter.

37. How analytics Process Your Request When you Create your Requests?

Answer:- Oracle BI server converts the logical SQL submitted by the client into

optimised physical SQL which is then sent to the backend database. Also in between it

performs various tasks like converting the user operations like user selections to form a

logical SQL, checking and verifying credentials, breaking the request into threads(as

Oracle BI is a multi threaded server), processes the requests, manages the cached

results, again converting the results received from the database into user presentable

form etc.

38. From where u Get the Logical Query of your Request?

Answer:- The logical SQL generated by the server can be viewed in BI Answers.

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

Answer:- 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.

40. What are Global Filter and how thery differ From Column Filter?

Answer:-

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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.

41. How to hide Certain Columns From a User?

Answer:- We can hide a column in Application access level security

Do not add the column in the report

Do not add the column in the presentation layer.

42. 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.

Hyperion IR has a drill anywhere feature where dont have to define and can drill to any

available column.

43. How the users Created Differs From RPD/Answers/Dashboards Level?

Answer:- RPD users can do administrator tasks like adding new data source, create

hirarchies, change column names where as Answers users may create new charts, edit

those charts and Dashboard users may only view and analyse the dashboard or can edit

dashboard by adding/removing charts objects.

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

Answer:-

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.

45. What is Guided Navigation?

Answer:- 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.

SCENARIOS

How change the column heading dynamically

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We can change the column heading dynamically by passing the presentation variable in

column heading, to achieve this follows following steps

1) Log into the Business Intelligence analytics with the link 

    http://Machine_name:port/analytics

    The port will be 7001 if OBIEE install with simple install option with default port

    configuration or it will 9704 if OBIEE is install with enterprise option default port

configuration

2) Click on New-> Dashboard Prompt

          

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3) Select the column prompt

  

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4) Select the Column Calendar Date from Sample Sale Lite subject area

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5) Set the presentation variable Date and save it

  

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6) Then go for report creation click New-> Analysis

  

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7) Pulled the column field to display on the reports

8) Click on right most button of field and select column property

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9) On column properties dialog box navigate over column format and select check box

Customize heading.              Set the presentation variable @{Date} in column heading

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10) Save the report and pulled it on Dashboard page and select the date from prompt

11) The column heading will change according to value select in the prompt

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Posted by yogi at 19:56 No comments:

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OBIEE Security Enforcement

OBIEE SECURITY ENFORCEMENT – LDAP AUTHENTICATION

AUTHENTICATION IN OBIEE

Some authentication methods used by Oracle BI server are

Database

LDAP

Oracle BI server (repository users) – I do not recommend this method for medium to

large implementations. It will be difficult to manage.

I will discuss on setting up LDAP in this article.

SETTING UP LDAP OR WINDOWS ADSI IN OBIEE

Microsoft ADSI (Active Directory Service Interface) is Microsoft version of LDAP server.

Most of the steps to setup of either Microsoft ADSI or LDAP server are similar. In either

case, you would need help from your network security group/admin to configure LDAP.

They should provide you with the following information regarding the LDAP server

LDAP server host name

LDAP Server port number

Base DN

Bind DN

Bind Password

LDAP version

Domain identifier, if any

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User name attribute type (in most cases this is default)

REGISTERING AN LDAP SERVER IN OBIEE

In Oracle BI repository, go to manage security.

Create a new LDAP server in OBIEE Security Manager

With the help from your network security group/administration, fill out the following

information

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Next in the Advanced tab, based on the kind of LDAP server you have and its

configuration, make the necessary changes.

For Microsoft ADSI (Active Directory Service Interface), choose ADSI and for all others

leave it unchecked.

Most of the times, Username attribute would be automatically generated. For Microsoft

ADSI It is sAMAccountName; for most of the LDAP servers it is uid or cn. Check with your

network security group/administrator on what is the username attribute for your LDAP

server. Make a note of the user name attribute you will need it later.

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Now we need to create an Authentication initialization block. In administration tool,

under Manage go to Variables.

Under Action, go to New -> Session -> Initialization Block

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Configure the session initialization block. Give it a name and click on Edit Data Source.

In the pop up window, choose LDAP from the drop down box and then click on Browse.

You can also configure a LDAP server here by clicking on “New”. In the browse pop up

window choose the LDAP server you would like to use.

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Next we need to create variables. User and Email are the common variables normally in

play.

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Upon clicking on OK, a warning pops up on the usage of User session variable (User

session variable has a special purpose. Are you sure you want to use this name). Click

yes.

Next enter the LDAP variable for username. sAMAccountName in the case of ADSI as

configured in the LDAP.

Next following similar steps create a variable for Email. In addition, depending on you

need, you can bring additional variables from the LDAP server.

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Posted by yogi at 19:53 No comments:

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Connection Pools – Best Practices

CONNECTION POOLS – BEST PRACTICES

Most of the times not much thought is given to defining connection pools while

developing rpd. Improperly defined connection pool would affect the OBIEE performance

and user experience. Here are some of the things to consider while defining connection

pool.

Change the default maximum connections. The default is 10. Based on your system

usage change the value that is more realistic to your system usage

Create a separate connection pool for execution of session variables

Create a separate connection pool for the execution of aggregate persistence wizard.

Remember that you need to give the schema user owner credentials for this connection

pool as the wizard creates and drops tables

If need be create a separate connection pool for VVIPs. You can control who gets to use

the connection pool based on the connection pool permissions.

Posted by yogi at 19:51 No comments:

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FRIDAY, 28 DECEMBER 2012

Mapping Analyst for Excel in Informatica 8.6 OBIA

Mapping Analyst for Excel in Informatica 8.6 OBIA

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Hi friends , hope you all have come across the Mapping Analyst for

Excel in Informatica Power Centre 8.6 version.I would like to just give a brief

introduction about the same.In the coming days we will discuss more about the same.

As you all know before when we start a DWH project we need to gather business

requirements from the client.It takes some time for us to analyze the functionality of the

project and then make that as a document in technical perspective for ETL. This process

is too tedious as a lot of valuable development time is spent gathering business

requirements and then translating them into technical specifications, and then

converting these  specifications to PowerCenter data integration mappings.So in order

to avoid this Informatica has come with a new feature called Mapping Analyst for Excel.

Mapping Analyst for Excel simplifies the complexity in mapping by directly converting

the data in the Excel into Informatica Mappings regardless of the format.This will mainly

help the Analyst.They can follow a specific template for defining the source and target

in the Excel and then send the same to the Developers who can directly convert this

template into Informatica Mappings and execute the workflows.

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Posted by yogi at 08:29 No comments:

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How to convert the date field in OBIEE report to a desired date format

How to convert the date field in OBIEE report to a desired date format?

CAST (expr AS type) is a conversion function in OBIEE that changes the data type of a

value or a null value to another data type.This is one solution to change the

datatype,but when I tried with this the column heading in report changed to different

colour and my client didn't liked that solution.So I tried another solution.Follow the

below steps and screenshots.

1.Go to Column Properties tab

Select column properties tab

2.Select Data Format tab

3.Check “Override Default Data Format” box

4.Select “Date Format” field dropdown as custom/as required in your report. If you

select “Date Format” field dropdown as custom then specify “Custom Date Format” field

as required in report.

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Posted by yogi at 08:28 No comments:

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How to convert the date field in OBIEE report to a desired date format

How to convert the date field in OBIEE report to a desired date format?

CAST (expr AS type) is a conversion function in OBIEE that changes the data type of a

value or a null value to another data type.This is one solution to change the

datatype,but when I tried with this the column heading in report changed to different

colour and my client didn't liked that solution.So I tried another solution.Follow the

below steps and screenshots.

1.Go to Column Properties tab

Select column properties tab

2.Select Data Format tab

3.Check “Override Default Data Format” box

4.Select “Date Format” field dropdown as custom/as required in your report. If you

select “Date Format” field dropdown as custom then specify “Custom Date Format” field

as required in report.

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OBIA Architecture and Functionality Overview

OBIA Architecture and Functionality Overview

The architecture for Oracle Business Intelligence Applications (OBIA) includes several

components.  Understanding these components is prerequisite to a successful OBIA

implementation.   A brief description of each component is included below the diagram.

OBIEE:

OBIA is a set of prebuilt reports for every business module like Financial, HR, Sales,

Order Management, etc.

In order to have pre-built reports we need to have prebuilt rpd (generic business logic).

The rpd is built on top of pre-defined tables (dimensions and facts). The tables reside in

a BI database(OLAP).

Informatica:

Prebuilt OBIA Informatica mappings are created to extract data from several data

sources (OLTP) and load to BI database (OLAP) tables.  These data sources include

Oracle EBS, JD Edwards, Peoplesoft, and other ERP systems.

A set of SDE, SIL and PLP together loads data into one BI fact or dimension table

SDE Mapping or Source Dependant Loads: Are used to extract data from and Data

Source to staging

SIL Mapping or Source Independant Loads: Are used to load data from staging to the

target OBI tables (dimensions and facts)

PLP or Post Load Processes: Are sometimes used to transform data after it is in a fact

table, or add to data after it is in a fact table.

Informatica structure:  An informatica workflow includes one or more sessions sessions. 

Each session includes one mapping.

A workflow is started that runs one or more sessions.  The logic of each session is

defined in a mapping.

DAC:

DAC acts like a trigger to run the workflows in Informatica.

DAC contains Execution Plans which can be scheduled or run any time. These Execution

Plans are designed to do an incremental or a full load.

Within each Execution Plan there are several subject areas, each subject area contains

all the tasks which are associated to workflows in Informatica that loads data to the

dimensions and facts to build the corresponding subject area.

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OBIA Architecture and Functionality Overview

OBIA - Naming Convention

Table

Table Types Used by the Oracle Business Analytics Warehouse

Table Suffix Description

Aggregate tables (_A) Contain summed (aggregated) data.

Dimension tables (_D) Star analysis dimensions.

Staging tables for

Dimension (_DS)

Tables used to hold dimension information that have not

been through the final ETL transformations.

Staging tables for Usage

Accelerator (WS_)

Tables containing the necessary columns for the ETL

transformations.

Dimension Hierarchy

tables (_DH)Tables that store the dimension's hierarchical structure

Dimension Helper tables

(_DHL)

Tables that store M:M relationships between two joining

dimension tables.

Staging tables for Staging tables for storing M:M relationships between two

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Dimension Helper

(_DHLS)joining dimension tables.

Fact tables (_F) Contain the metrics being analyzed by dimensions.

Fact Staging tables (_FS)

Staging tables used to hold the metrics being analyzed by

dimensions that have not been through the final ETL

transformations.

Column

Suffix Description In Table Types

_CD Code field_D, _DS, _FS, _G,

_GS

_DT Date field_D, _DS, _FS, _G,

_DHL, _DHLS

_I Language Independent Code. 1) _D, _MD

_ID_ID columns are used in _FS tables. They correspond to the

_WID columns of the corresponding _F table._FS

_FLG Indicator or Flag._D, _DHL, _DS, _FS,

_F, _G, _DHLS

_WIDIdentifier generated by Oracle Bl linking dimension and

fact tables, except for ROW_WlD._F, _A, _DHL

_NAMEName corresponding to the code column (columns ending

with _CODE)_D, _F, _A

_DESCLong Description corresponding to the code column

(columns ending with _CODE)_D, _F, _A

Posted by yogi at 23:14 No comments:

MERGE Two Repository in OBIEE 11G

Hi All,

Here are the simple steps to merge two repository in obiee 11g

You should have three rpd's for merging

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1) Your Current RPD.  (BISAMPLE.rpd)  >>Current RPD<<

2) The RPD to be merged (the one you newly worked on) - sandeep.rpd >>Modified

RPD<<

3) Dummy RPD. In My case dymmy.rpd  

If you don't have a dummy. rpd , create a new rpd from the admintools (do not import

metadata).

ok now we are all set to start the merging.

Step 1: Open your Current RPD, ie BISAMPLE.rpd in my case and select the merge

option.

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Step 2: Provide the details of RPD as given below.

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Select dummy.rpd as your original rpd and Sandeep.rpd as the modified rpd

and click next >>

Step 3: Define Merge Strategy

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In this case select Decision = Current

Click next  finish >>>

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The repository merge is now complete.

variables in OBIEE 11g.

There are basically 4 different types of variables in OBIEE 11g.

Session Variables

Repository Variables

Presentation Variables

Request Variables.

Session Variables:

As the name suggests, session variables are created during the creation of session i.e.,

as soon as a user logs into the BI server.  So, Every login has its own session variable.

There are two types of session variables

 System (which are defined by OBIEE and are reserved)

Non-System which are defined by developers.

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Session Variables can be created only through Oracle BI Administration Tool.

Referencing session variable:

For displaying session variables, we should use

@{biServer.variables['NQ_SESSION.VariableName']} .

For using session variables in expression, we should use

VALUEOF(NQ_SESSION.“VariableName”).

Repository Variables:

 A repository variable is a variable that has a single value at any point in time.

There are two types of repository variables

Static (which changes only if admin or developer changes it value)

Dynamic ( value is refreshed using a query)

Repository variables can be created only through Oracle BI Administration Tool.

Referencing repository variable:

For displaying repository variables, we should use @{biServer.variables.VariableName}

or @{biServer.variables['VariableName']}.

For using repository variables in expression, we should use VALUEOF(“VariableName”)

for static variable and for dynamic variable VALUEOF(“Dynamic Initialization Block

Name”.“VariableName”).

Presentation Variable:

A presentation variable is a variable which can be created as a part of creation of

dashboard prompts. Dashboard prompts must be either Column Prompt or Variable

Prompt.

The value of presentation variable is set by the prompt for which it is created (upon user

selection).

Referencing presentation variable:

For displaying presentation variables, we should use either

@{variables.VariableName}[Format]{DefaultValue}  or

Format and DefaultValue are optional

Format is useful to format the data for e.g., for Date, format can be MM/DD/YYYY. Note:

Default Value is not formatted.

@{scope.variables['VariableName']}.

Scope should be used if you create variables with same name.

Scope can be analyses, dashboard etc.

Order of precedence is analyses, dashboard pages, dashboards.

For using presentation variables in expression, we should use @{“VariableName”}

{DefaultValue}. Default value is optional.

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Request Variable:

Request Variable is used to overwrite the value of session variable and it happens only

during request initiation to the database from column prompt.

Can be created only during the creation of column prompt.

1.What is the difference between OBIEE 10g and OBIEE 11g?

A Database Repository must be created before installing OBIEE by using Repository

Creation

Utility(RCU) tool

OBIEE 11g uses a WEBLOGIC server as Applictaion server whereas OBIEE 10g uses OC4J

Many configuration settings (such as uploading a repository into BI server) can be done

using EM

OBIEE 11g displays table names and COLUMN NAMES while mapping whereas OBIEE

10g

displays only table names

In 10g Users and Groups(or Roles) are created in repository whereas in 11g Users and

Groups are

created in EM

Groups no longer exist and are replaced by Application roles. Data level security is

implemented by

using Application roles to which users belong to.

In Presentation Catalog, AuthenticatedUser role is used instead of Everyone group

We can model LOOK UP TABLE is repository

Creating hierarchy in Presentation layer

New time series functions PERIOD ROLLING and AGGREGATE AT is introduced

TIME SERIES functions can be created in the front end also

AGGREGATE PERSISTENCE WIZARD creates indexes automatically

SESSION VARIABLES are intialised only when they are used

In addition to the existing views, Map View is introduced in 11g

RAGGED and SKIPPED HIERARCHY are supported in 11g

KPI's and SCORECARD's are introduced in 11g

ACTION LINKS, MASTER-DETAIL reports, SELECTION STEPS are introduced

SELECT_PHY SICAL is supported

REQUESTS are renamed as ANLAY SIS

IBOTS are renamed as AGENTS

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CHARTS are renamed as GRAPHS

2. What is an Alias table and why is it used?

An alias table (Alias) is a physical table which references a different physical table as its

source

Advantages of using alias table:

It allows you to reuse any existing table more than once, without having to import it

several times

It can be used to avoid circular joins by setting multiple tables each with different keys,

names or joins For example: Order date and Shipping date may reference to same

column in the time dimension table. By using alias you can create two different

tables OrderDate and ShippingDate

It can be used for best practice naming conventions as you can rename the table and

leaving the original physical table as it is

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