Tuesday 15 September 2015

OBIEE Analysis Interview Questions


ANALYSIS

1.       What are the column properties?

Style, column format, data format, conditional format, interaction, write back

 

2.       What is the use of hide column option?

It is useful to hide unnecessary columns

 

3.       Can we sort month column as per calendar ascending order ?

Yes. By using the month code column we can sort as per calendar ascending order and we can hide the month code column if we don't want it in the report

 

4.       Can we format part of the column title?

Yes. in OBIEE 11G by using HTML tags we can do it

for ex:- cal year is the column name. we want to make only year bold we can make it as cal<B>year</B>

 

5.       What is suppress option?

It is useful to hide duplicate values in report

 

6.       What is data format?

It is useful to convert one format of data into another format

ex:- if we want convert the rupees into dollars or to any other currency we can do it.

 

7.       What is Conditional Formatting?

It is useful to format data based on some condition

ex:- if we want to divide the business based on sales then

dollars-->column properties-->conditional formatting

dollar's value is less than 100000-->select color as Red

dollar's value is between 100000, 200000-->select color as Yellow

dollar's value is greater than 200000-->select color as Green

we can see the data of dollar values with colors

 

8.       What is Interaction?

It is useful to apply action links, drill options on column headings and column values

 

9.       What is Write back?

In Reports of Answer you can give a column as updateable and then view the reports, this option is called write back.

 

10.   What is BIN?

Bins are useful to combine the values for the column into sets and also useful to group the data

OBIEE CATALOG INTERVIEW QUESTIONS

WEB CATALOG
  1. What is meant by Web Catalog?
    It is a container (or) folder structure which is useful to store reports, dashboards, KPIs, score cards, user profiles etc...


  1. Is there any other names for web catalog?
    yes. web catalog is also known as BI presentation catalog


  1. Which server manages the web catalog?
    web catalog is managed by Oracle BI Presentation Server


  1. What are the steps we have to follow while creating web catalog?
    In creating web catalog we have below steps
      1. Configure EM(Enterprise Manager)
      2. Restart oracle BI presentation server
      3. Confirm catalog in catalog folder


  1. Where can we find the catalog path in EM?
EM Core application deployment repository lock and edit configuration under BI Presentation Catalog we can find the whole path of the catalog


  1. What is the default location of the catalog?
    <OBIEE_HOME>\instances\instance1\bifoundation\OracleBIPresentationServicesComponent\coreapplication_obips1\catalog


  1. When we restart OBIPS from where it can read the catalog, how it works?
    Whenever we started oracle BI presentation server it will read instancecofig.xml file and it picks the catalog name from file and verifies it is available in catalog folder (or) not. If catalog is available with same name then it will load else it will create new one


  1. What is the log file for OBIPS and where can we find it?
    The Log File of Oracle BI Presentation server is THE MAXIMUM VERSION OF THE SAWLOG and it is available in below path <OBIEE_HOME>\instances\instance1\diagnostics\logs\OracleBIPresentationServicesComponent\coreapplication_obips1


  1. Is there any folders contained by catalog, if yes what are they and where can we find it?
    Catalog contains three folders
    1. Shared folder or Public folder
    2. Users or My folders or personal folders
    3. System
      These three folders we can find in below location <OBIEE_HOME>\instances\instance1\bifoundation\OracleBIPresentationServicesComponent\coreapplication_obips1\catalog\SampleAppLite\root  


  1. What is the purpose or use of shared, my folder, system  folders?
    Shared Folder:
    This folder is useful to share reports or dashboards or KPIs..etc to end users or business users
    we can't save any reports directly in shared folder, first we have to create a new folder under shared folder then save the reports or dashboards
    My Folder: 
    This folder is personal folder .it will be created for each and every user separately with the name of   user when ever first time he signed into analytics If a user save a report in this folder that cannot be  accessed by any other user . These folders are useful to save partially developed reports
   System:
   It is useful to store system level properties.
   This folder is not accessible from analytics page


 

 

Monday 24 August 2015

CACHE MANAGEMENT

                                                                      CACHE MANAGEMENT
  1. What is Cache Management?
               Monitoring and managing the cache is called cache management.
  1. How many types of Caches we have in OBIEE?
        In OBIEE we have 2 types of Cache:
                   1.Oracle BI Presentation Server Cache


2.Oracle BI Server Cache
              
3. Could you please tell me what is the report order of execution and where report result will be stored actually?
          The report order of execution is
1. OBIPS cache
2. OBIS cache
3. DB cache
                And the report result will be stored in OBIPS cache and OBIS cache
  1. What is advantage of Cache Management?
                  We are able to improve the Performance by reducing time to execute it      
                 and reducing time to create the physical sequel
  1. Let me know one thing actually, what are the differences did you observed running a report twice at the time of cache?
       Running a Report First Time:
       1. Logical SQL based on RPD BMM layer
       2. Physical SQL based on Physical layer joins
       3. This Physical SQL executing Connection Pool corresponding DB
       4. Result showing to user and also it stores result in OBIPS Cache and OBIS   
           Cache
     Running a Report Second Time:
  1. Logical SQL based on RPD BMM layer
  2. The logical SQL corresponding cache will be shown to the user


  1. How to skip OBIPS cache for particular report?
                 Advance Tab: By pass OBIPS cache enable
                 
  1. How do I disable cache for only two particular tables?
                 In physical layer, right click on the table there we will have the option
                 Which says cacheable and here you have to deselect the check box
                  
  1. What is cache management? How do you implement auto cache management?
               Cache Management:
              →Process to maintain cache for performance and update at certain   
                  Duration
             →Auto cache management can be attained by setting Event Pooling Table
  1. Could you please tell me how do you purge cache by subject area or cache by query?
               Admin Tool: Manage→Cache→Purge    
               
  • You can purge all the cache
  1. Let us assume we have two reports on that one report is cacheable and other is not cacheable, how the request will happened?
The request will not be cached.
  1. What is advantages of cache?
               1.  Saves the result of queries in cache files
         2.  Enable OBIS to satisfy subsequent query request without having to   
               Access back-end databases
         3.  Less network Traffic
         4. Improves Performance
  1. What is Disadvantages of cache?
               1. There is chance to get stale data.
               2. Memory wasted
  1. What is the use of Enable BI server cache?
            Enabling the server cache can greatly improve performance by enabling   
            Users who share data visibility to retrieve row sets from queries that   
            Have already been run at the loss of the Possibility of seeing stale data.
  1. If the cache is shareable among all the users are not?
             → Yes
  1. Tell me some of the parameters did you observed in cache?
                User, Use count, last used, Repository, Business Model etc.  
    
    16. Tell me one thing I have two users X1 and X2 and I want to purge a U1    
Related cache how it is?
            →Cache manager window→Select required caches and purge
  1. I have run a three reports i.e.  Customers, Products, calendar with orders Fact and then I want to delete customer table cache, how it is?
          Cache manger window→Physical tab→Navigate to customer table   
          →Edit→Purge
          Note: Notice that the customer cache will be deleted.
 18. What is purging?
      The process of removing query cache entries is called purging.
 19. What are the purging methods?
                            1. Manual.
                            2. Persistency
                            3. Event Pooling Table
                            4. ODBC functions
  20. What is manual Purging?
               For this manual Purging human interaction is required
  21. What is Persistency time purging?
               It is useful to purge cache based on fixed time. To provide this setting we   
               need to know accurately the tables refresh frequency.
22. What is query caching?
           It is used to save the result of query in cache file and reuse for similar
           Queries.
23. What are the advantages of query caching?
Answer:  1. Improve query performance
               2. Less network traffic
               3. Reduce DB processing
              4. Reduce OBI server processing
24. What is cache Hints?
          A cache hints means that the server was able to use cache to answer the  
         query and did not got to the database at all.


25. How you are doing the cache purging in your Project?
           In my project all the ETL jobs are running every day mid night, so that in
           my project we set the persistency time for all physical tables one day.
26. When will do the cache purging?
           If new data comes into Data warehousing then we need to cache purging
           Otherwise the report don’t shoe the new data. If the report hitting the  
          Cache.
27. How to disable cache?
              1. Login to EM
              2. Click on Core-Application under BI
              3. Click on capacity management tab
             4. Click on Performance sub tab
             5. Click on Lock and edit configuration
             6. Deselect the cache enable check box
            7. Click on apply button
8. Click on activate changes button
9. Restart the services
28. What is the use of LOG-LEVEL?
           The amount of log information to be specifies for a user, generally we
           can use level-2
29. How many ways to do cache purging?
        Manually: In Admin tool by using the cache manage to purge the cache
                            entries.
        Automatically: We have four types of ODBC functions, those are useful
                              to purge cache programmatically & those functions are
                1. SA purge all cache.
                2. SA purge cache by db.
          3. SA purge cache by table.
          4. SA purge cache by query.
                          It is an accurate method to purge the cache. Normally these              
          functions will be executed by ETL-team using their post load option.


30. What is Presentation server cache?
          1. The presentation server caches the result of the queries OBIPS users the   
              request key and logical SQL string to determine if subsequent queries can       
              use cache result.
         2. It will be unique for Particular Session
31. What is SEED-CACHE?
          1. Inserting cache into cache folder is called seed cache.
          2. Seeding is the process of pre calculating the cache with queries that are
               Known to generate cache hits.
          3. Helps improve query performance.
32. Cloud you please tell me, how many ways to purge the cache in   
       Presentation services?
       1. Refresh Icon Dashboard
       2. Clear my selections
       3. Manage session→session management →close all cursors
33. What type of purging methods you are used in Project?
       1. ODBC Functions (Programmatically)
        2. Event Pooling Table
        Note: Tell them to above two methods first priority goes to ODBC
34. What is Difference between Persistency time and EPT?
          In EPT we have the new records then purging happened, whereas the above  
          Persistency is time fixed.
35. What is Difference between EPT and ODBC functions?
         In EPT stale data is available to overcome this problem we will go for ODBC     functions.
36. What is Manual Seeding?
          Navigate to the report in the catalog →click on the report →then
          automatically cache will be created.
37. Could you please tell me, how will you perform EPT in your project?
           1. Import table S_NQ_EPT in physical layer
           2. Defining table S_NQ_EPT as event Pooling table.
38. What are the parameters enabled while cache time?
   1. Enable BI server cache enable, maximum cache entry size=20,
        Maximum cache entries=1000
2. Global cache, global cache path, global cache size


39. I want to disable the cache entire environment?
If you want to disable OBI PS cache for entire environment,
We need to change tag in INSTANCECONFIG.XML file LOCATION:instance\instance1\config\oracle BIPS      component\coreapplication_obips1\instanceconfig.xml file
           <Server Instance>
            ___________________
<cursors>
<ForceRefresh>True/ForeceRefresh>
</cursors>
__________________
<server instance>


40. While generating a report I don’t want to read the OBIPS cache? How you will do this?
                    If we click report refresh button it will not read OBIPS cache, directly it   
                    will go for OBIS cache


41. Could you please tell me what the difference between OBIPS and OBIS   
      cache?
              OBIPS cache is temp cache and whereas OBIS server cache will not be    
           deleted with OBI server start or restart