QV30 Qlikview Interview Questions

Qlikview is powerful BI tool used to create report, dashboards and this tool is capable of showing real time report or snapshot based reports.

Real time report - data is directly coming from OLTP database
Snapshot reports - Qlikview collect data in QVD's, which needs to refresh on daily/weekly basis

Below are the some of qlikview questions which can be asked by any interviewer.

QlikView Interview Questions:


QlikView Architecture:
1. Optimized and Un-optimized QVD Load Situations?
2. 3 tier architecture implementation
3. How does QlikView stores data internally?
4. Restrictions of Binary Load?
5. How are NULLS implemented in QlikView?
6. How do you optimize QlikView Application? (What tools are used and where do you start?)
7. What is the difference between Subset ratio & Information Density?

QlikView Scripting:
1. What is the difference between ODBC, OLEDB & JDBC?
2. What is the use of Crosstable prefix in QlikView Load Script?
3. What is Mapping Load & ApplyMap()?
4. What is the difference between Map Using and Mapping Load?
5. Synthetic keys in QlikView and how & when to avoid them?
6. Difference types of Joins in QlikView?
7. What is the difference between Join and Keep?
8. How do you use Having clause (SQL Equivalent) along with Group By in QlikView?
9. Explain IntervalMatch function in QlikView?
10.Explain Concatenation, No Concatenation & Auto Concatenation?
11.Explain how to implement Incremental Load?
12.What is Circular Loop and how do you avoid it?
13.Explain Exists() function in QlikView and when do you use this function?
14.What is Generic Load in QlikView?

QlikView Expression Language / UI:
1. Explain Aggr Function?
2. What is the use of FirstSortValue in QlikView?
3. What are Set Modifiers and Set Identifiers?
4. What is P() & E() and where do you use them?
5. What is the difference between ValueList() and ValueLoop()?
6. What is Partial Reload? Why do you use “ONLY” Qualifier?
7. Difference between Cyclic Group & Drilldown Group?
8. Explain Alternate States? Where do you use them?

QlikView Security:
1. Describe Section Access Architecture?
2. Difference between Authentication & Authorization in QlikView? How to implement them?
3. Difference between File System Security vs Section Access?
4. Explain “Strict Exclusion” while implementing Section Access? What are the implications of not using them?
5. How do you implement Section Access on hierarchy based data?


QlikView Server and Publisher:
1. What are the multiple protocols defined for client communication with QVS?
2. Explain different communication encryptions for Windows Client & AJAX Client?
3. What is the use of Anonymous User Account in QVS?
4. What are the different types of CALS and Explain them?
5. What are the different editions of QlikView Server?

General:

1. Difference between RDBMS and Associative Database?
2. Ragged hierarchies in Data Ware Housing?
3. Explain EAV data Modelling Technique?
4 What are slowly changing dimensions?



Questions About Roles

1. Whats your role in your project
2. Whats your daily activity in your project
3. Requirement Gathering
4. One can ask About your project
5. What is the major KPI s in your project
6. What is Dashboard
7. Which  architecture are you using in your project
8. What type of schema are you using in your project
9. Difference between Star and Snowflake schema
10. What is Peek, Previous, Apply map, Interval Match
11. Whats is the difference between Pick and Match
12. What is Fuzzy search
13. How many charts are you used till now
14. Have you used macros in your project and why
15. Whats the difference between QV versions
16. Have you used Alternate states and why
17. How many dimensions are used in Guage Chart
18. What is set analysis
19. Best data modelling techniques
20. You have any knowledge about QV server and Publisher
21. What is Incremental Load
22. Have you Create Ad-hoc reports in your project And how
23. Any knowledge about Data Island
24. DMS authorization
24. Section Access
25. Conditional enabling
26. Difference between join and keep
27. Difference between Concatenate and join
28. Binary Load, Preceding Load, Partial Load
29. How many ways you can maintain to store the QVD's

1. Qlikview features
2. What is Circular loops
3. What is Synthetic key, is it good or bad having?
4. What P() and E() in Set analysis?
5. What is Comparative analysis?
6. What is Mekko chart and what is the difference between bar and Mekko chart?
7. What is the difference between Pivot, Straight and Table box?
8. How you connect to Database?
9. What are the various data sources for Qlikview?
10. What is partial reloading?
11. How you refresh you dashboards periodically?
12. What are the different types of CALs available?
13. What are the various joins available in Qlikview?
14. How you use Macros in Qlikview?
15. How you optimize Qlikview dashboards?
16. What care should be taken while designing a datamodel?
17. How you test your Dashboard?
18. Types of authorization in Qlikview?
19. Difference between Join and Concatenate?
20. What is NoConcatenate?

failed to load the jni shared library

I am here listing some of the error while installation of Spago BI studio, i am getting these error and here i am writing the problem and solution, so that other can not stuck cause of small error.

After installation of java 1.6 from post, i tried to start SpagoBIStudio_5.1.0 using below command

SpagoBI.exe -vm "C:\Program Files (x86)\Java\jdk1.6.0_30\bin"

it failed with error "failed to load the jni shared library"

Problem :
incorrect version of java used

Solution :
I am trying to start 64 bit version of spagoBI server with 32-bit version of java.
install 64-bit versionof java and then try below command

SpagoBI.exe -vm "C:\Program Files\Java\jdk1.6.0_30\bin"

java was started but returned exit code 13

java was started but returned exit code 13

This problem occur during startup of SpagoBIStudio_5.1.0 studio. In my case i tried to start SpagoBI studio for makeup of my reports, but it never start. Then i go through the logs generated by application and it gives error "java was started but returned exit code 13", after working with colleagues and google i identified the solution finally, please look the solution below.


Problem:
I have installed java (1,7/1.8) on system, because of spagoBI compatibility issue, was using incorrect version of java.

Solution:
Install correct version of Java (in my case it is 1.6)

Add Random Data in Spreadsheet

There can be various ways to add random data in spreadsheet, sometime we need high number of records to start a unit testing, but dev application not having too much of data initially. Here is the example how to add number of records in spreadsheet, i my case best way is use macro code.

To add random data in spreadsheet you can use macro code and you have to save spreadsheet "macro enable workbook" if you are using higher version of office, advantage to use this code is no more manual work. Use below code to generate data.

Public Sub ran()
Dim b As Range
    For i = 1 To 800000
        Dim r As Double
        r = Int(Timer * Rnd())
        Cells(i, 20).Value = 0
        Cells(i, 21).Value = "USD"
        Cells(i, 22).Value = ""
        Cells(i, 23).Value = "A clever fox just jump over the lazy dog"
        Cells(i, 24).Value = r
    Next i
End Sub

Dynamic data generated in "r" variable and rest of data is static.

Best way to run macro
1. Save spreadsheet in Macro enable workbook
2. Record the Macro
3. Stop the Macro
4. Then go to Macro > and Edit
5. Copy and paste above code in popup window
6. and run the macro code

Talend Startup Error

My machine is installed with java 1.7 and 1.8 both and i have moved to environment setting of computer and observed that JAVA_HOME environment variable set to 1.7., When i tries to to start the talend ETL tool on my machine, it throws the version error. Here i am writing this article to resolve this error. You can like, share, and add your value able comments in this post if it helps you.

Here i am trying to start talend but it throws error:

"The Studio does not support Java 8. Java 7 is the recommended JVM version to be used"

Now how to start Talend on machine if both java version is installed on your machine

Solution

As Talend the version i am using is not supportable on java 8, so i need to start talend through cmd assigning it java 7, so that it can start, let's use below commands and see if it works or not.

• Open Cmd
• Move to installed directory of Talend and run below command
• TOS_DI-win32-x86.exe -vm "C:\Program Files (x86)\Java\jdk1.7.0_65\bin"

Xampp Starting Error

One of the friend came to me and ask if you will help me out, i said why not. when i asked about the problem he told my xampp server was not working. I was think in my mind i was not aware of this tool, then how i can help him. However we sit together and started looking into the problem.

We were having
- Window 7 on 32 bit laptop
- xampp server installed by friedn him self

We started and try to start xampp and getting below error

"Port 80 in use by "unable to open process" with PID 4:

Error clearly mention, Apache tomcat want to use 80 port and it is being used by PID (Process ID) 4

How to proceed:

• Open Task manager
• Look for the PID with number 4, probable it will be "NT Kernel and system"
• Open CMD and check the processes that are running with port number 80

netstat -o -n -a | findstr 0.0:80

• After searching on google, came to know that the PID process is related to SQL server Reporting server. 
• Go to services
• Stop all services related to SQLServer
• Stop and start services for apache and mysql
• It Works!!!!

Other Possible Processes :

Skype

IIS

VMWork Station