Hyperion EssBase Interview Questions & Answers

ESSBASE Interview Questions

What are the different types of LOG Files?

So many log files are there in essbase, but the important log files are

• Application log
• Essbase.log
• Configtool.log
• eas_install.log
• essbaseserver-install.log

Suppose we have assigned Generation 2 and Generation 4 as of now and think of adding generation 3 later some time. Can we build the dimension?

No. If gen 2 and gen 4 exists, we must assign gen 3.

What are attributes?

A classification of a member in a dimension. You can select and group members based on their associated attributes. You can also specify an attribute when you perform calculations and use calculation functions. Eg: The database in Sample Basic which has product dimension has some attributes like size, package type, and flavor. We can add these attributes to the dimensions where we can retrieve the data like for example to retrieve “coke with 8 Oz with bottles”, this is useful for generating reports.

Why do objects gets locked and when does this happens?

Objects gets locked to prevent users to make simultaneous and conflicting changes to Essbase database objects. By default whenever an object is accessed through Aministrative services console or Excel spreadsheet add-in, it gets locked.

What is the difference between UDA’s and Attribute dimensions?

Attribute dimensions provides more flexibility than UDA’s. Attribute calculations dimensions which include five members with the default names sum, count, min, max and avg are automatically created for the attribute dimensions and are calculate dynamically.

How does Attribute dimensions and UDA’s impact batch calculation performance?

• UDA’s- No Impact as they do not perform any inherent calculations.
• Attribute dim- No Impact as they perform only dynamic calculations.

What are different types of attributes?

Essbase supports two different types of attributes.

• User-Defined attributes
• Simple attributes

User-Defined attributes: The attributes that are defined by the user.

Simple attributes: Essbase supports some attributes, they are: Boolean, date, number, and string.

What are filters?

A method of controlling access to database cells in essbase. A filter is the most detailed level of security, allowing you to define varying access levels different users can have to individual database values.

What is TB First and TB Last?

• TB First: in the Sample.Basic database, the accounts member Opening Inventory is tagged as TB First. Opening Inventory consolidates the value of the first month in each quarter and uses that value for that month’s parent. For example, the value for Qtr1 is the same as the value for Jan.
• TB Last: in the Sample.Basic database, the accounts member Ending Inventory is tagged as TB Last. Ending Inventory consolidates the value for the last month in each quarter and uses that value for that month’s parent. For example, the value for Qtr1 is the same as the value for Mar.

How can we display UDA’s in reports? How do they impact report report performance?

UDA’s values are never displayed in the reports and hence do not impact report performance.

How does Attribute dim impact report performance?

They highly impact the report performance as the attributes are calculated dynamically when referenced in the report. For very large number of att dim displayed in the report, the performance could drastically reduce.

While loading the data, you have applied both the selection criteria as well as rejection criteria to a same record. What will be the outcome?

The record will be rejected.

How is data stored in the Essbase database?

Essbase is an file based database where the data is stored in PAG files of 2 GB each and grows sequentially.

Can we have multiple metaoutlines based on one OLAP model in Integration services?

Yes

What are LRO's( Linked Reporting Objects)?

They are specific objects like files, cell notes or URL's associated with specific data cells of Essbase database. You can link multiple objects to a single data cell. These linked objects are stored in the server. These LRO's can be exported or imported with the database for backup and migration activities.

What are the three primary build methods for building dimensions?

• Generation references
• Level references
• Parent-Child references

How does UDA's impact database size?

There will be no impact on the database as the UDA’s doesn’t store data in the database.

Can we have an metaoutline based on two different OLAp models?

No.

Can we create UDA’s and apply it to Dense as well as Sparse dimensions?

Yes

Types of Partitions available in Essbase?

Three types of partitions are there.

• Transparent partition: A form of shared partition that provides the ability to access and manipulate remote data transparently as though it is part of your local database. The remote data is retrieved from the data source each time you request it. Any updates made to the data are written back to the data source and become immediately accessible to both local data target users and transparent data source users
• Replicated Partition
• Linked Partition

What is hybrid analysis?

Lower level members and associated data remains in relational database where as upper level members and associated data resides in Essbase database.

Hyperion Interview Questions

Why top-down calculation less efficient than a bottom-up calculation?Being less efficient, why do we use them?

In the process it calculates more blocks than is necessary. Sometimes it is necessary to perform top-down calculation to get the correct calculation results.

On what basis you will decide to invoke a serial or parellel calculation method?

If we have a single processor, we will use serial calculation but if we have multiple processors we can break the task into threads and make them run on different processors.

While loading the data, you have applied both the selection criteria as well as rejection criteria to a same record. What will be the outcome?

The record will be rejected.

How can you display UDA's in reports?

UDA's values are never displayed in the reposts and hence do not impact report performance.

What are the specified roles other than Administrator to view sessions, disconnect sessions or kill users requests for a particular application?

You should have the role of Application manager for the specified application.

What is block locking system?

Analytic services(or Essbase Services) locks the block and all other blocks which contain the childs of that block while calculating this block is block locking system.

What are the three options specified in Username and Password management under security tab in Essbase server properties?

1. Login attempts allowed before username is disabled.
2. Number of inactive days before username is disabled.
3. Number of days before user must change password.

Can we have multiple databases in one single application?

Yes. But only one database per application is recommended.

Depend on which database that you are going to create.

For Example: If you are creating ASO then we can’t create more that 1 db per application. If you are creating BSO then you can create more than 1 db per application

How is data stored in the Essbase database?

Essbase is an file based database where the data is stored in PAG files of 2 GB each and grows sequentially.

We have created an application as unicode mode. Can we change it later to non-unicode mode?

No

What are the types of partitioning options available in Essbase?

1. Replicated partition.
2. Transparent partition
3. Linked partition.

Dynamic calc decreases the retreival time and increases batch database calculation time. How true is the statement?

The statement should be just opposite. As dynamic calc members are calculated when requested, the retreival time should increase.

What is the role of provider services?

To communicate between Essbase and Microsoft office tools.

A customer wants to run two instances of an Essbase server on a same machine to have both test environment and Development environment on the same server. Can he do that?

Yes. We can have multiple instances of an Essbase server on a single machine and there will be different sets of windows services for all these instances.

Why top-down calculation less efficient than a bottom-up calculation?Being less efficient, why do we use them?

In the process it calculates more blocks than is necessary. Sometimes it is necessary to perform top-down calculation to get the correct calculation results.