Question.1 In an organization, data is updated monthly. Few thousand rows of data get added every
month to the existing tables. How you will load this data so that most updated data is reflected in the dashboard?

Answer: This data load can be done by creating an incremental load script. Using incremental load one can load only the updated rows of data.

Question.2 Recently we merged into a new company. We want to merge their employee data into our employee table. How can we achieve this?

Answer: Both the tables should have the same structure. You can load both the tables in Qlikview and concatenate them. This will append new employee records into the existing employee table.

Question.3 We have different departments developing dashboards. How to make sure that dashboards will show a single version of the truth and enterprise solution is delivered

Answer: Following practices will ensure the enterprise level of implementation

• The data model should be created once and should be included in the presentation layer by the use of Binary Load.
• Use QVDs for data storage and extraction in QlikView.
• Create Master QVDs for the data which can be reused by different teams.Examples for such QVDs can be Master calendar or Organization Info.
• Data source connection info should be kept in a text file and should be included in the dashboard using the Include statement.
• All standardized calculations should be maintained outside the dashboards by using variables. All commonly used calculations/variables should be kept in a text file or excel file. This calculation variable file should be included in the dashboard using the Include command.
• Look and feel of the dashboard should be the same. Create a QlikView template file which should be used by all the developers to create dashboards.
• Create a dashboard review board that will review all the dashboards before
  moving to production.

Question.4 An organization has around 100 users. What kind of CALs /license configuration should be implemented?

Answer: CALs should always be assigned based on the requirement of the users. We should know how users will be utilizing QlikView and how frequently. Users accessing the QlikView dashboards on a daily basis should get Named CALs. The more infrequent users can share the sessions CALs.

Question.5 How to setup QlikView development environment?

Answer: For ease and organized QlikView development

• Folder structure should be setup. This folder structure should have folders for

1. Apps – This folder contains Qvw files.
2. Data – This folder should contain subfolders for all the data, such as excel files, text file, QVDs etc.
3. Include – This folder should contain files to be included i.e. database connections, variables, any other.
4. Template – This should contain QlikView template files. There can be more than one template file based on the screen resolution.

• QlikView Desktop Settings should be configured to Generate log files, save before reload and other require settings.

Question.6 What common tasks can be performed using QlikView management console?

Answer: Some of the tasks performed using QMC are

• Connect to QlikView Server.
• Create data reload and distribution tasks.
• Schedule triggers to run the data load and distribution tasks at a specified time.
• Monitor status to view the success and failures of the different tasks.
• Monitored various services in the QlikView Server environment.
• Implement security and data reduction.

Question.7 How to implement QlikView multi-developer environment?

Answer:Multi-developer environment is required when the number of dashboards are to be developed by different developers.
In such an implementation, the team can be divided into data modelers and dashboard designers. Alternatively, one complete dashboard can be assigned to a single developer. But when the dashboard is huge then multiple developers can work on the same dashboard.
There can be many ways to implement such scenarios

• Data modeler/s create data models.
• Binary load is used by the dashboard developers to incorporate this data model scripts in the dashboard.
• If the dashboard is big, developers can be assigned to design specific sheets or
  charts.
• Team lead or a person assigned can merge all the separate charts into one main dashboard by copying and pasting.
• To manage such an environment, shared folders can be created.

Question.8 How to test a QlikView application?

Answer: QlikView application should be tested at multiple levels. If multi-tier data architecture is implemented, then extract layer, transform layer and presentation layer should be tested.
The basic principle is to always compare against the source data

• In Extract layer, after each table is loaded. Check it against the original data source. Check the count of rows in QlikView table and the source table.
• In Transform layer, check against the source table. If source is a database then write SQL queries to compare the results. Check aggregations after the transformation is done in QlikView tables.
• In the final data model, check for Information density and subset ratio. Information density gives the number of Not-Null records as compared to the total number of records in the table. Subset ratio is the number of distinct values of a field in a table as compared to the total number of distinct values of this field in other tables.
• Create a Table box of the table loaded and export it to excel to perform data
  validations.
• In the presentation layer, compare visualization created with the user requirements. To test calculations and aggregations, create Text Object to display calculations and aggregations.
• Check the aggregations in the charts by writing SQL in the database. For excel data sources, use excel filters and formulas.

Question.9  What should be the size of a QVD or QVW?

Answer: The size of the QVD and QVW depends on the specific requirement. There is no fixed size. The size of the dashboard depends on the data, objects and functionality of the dashboard.

Question.10 How you will open a QVW bigger than 4GB in size?

Answer:

If the dashboard size is larger than the RAM size of your computer, then you can open it on the server which will have more RAM.
Alternatively, if development is in progress and you don’t need the complete data, then perform limited load by using the debug option of the script editor.

Question.11 How much time it takes to create a dashboard?

Answer: There is no fix or set time to create a dashboard. Dashboard creation time always depends on the complexity of the requirement. Simple dashboards can be created in few minutes.

Question.12 What best practices should be followed in QlikView data modeling?

Answer: Use the following to create an effective data model

• Use QVD for good performance.
• Create 3 tier data architecture viz. Extract layer, transformation layer and presentation layer.
• Rename data source columns to give user friendly names.
• Remove synthetic keys and loops.
• Perform all the complex calculations in the script.
• Create Master calendar to handle dates.
•  Use optimized load in the presentation layer for better performance.

Question.13 In a multiple-tier QVD architecture, you have extract layer and transform layer. Which
layer will have a smaller QVD size?

Answer: Transform layer will have a smaller QVD size. In the transform layer, some transformation or filters must have been applied. Extract layer generally contains raw data.

Question.14 How to performance tune QlikView data model and dashboard?

Answer: Some of the ways to improve performance is to

• Use QVDs where ever possible.
• Reduce number of tables by using Mapping load, concatenate, join, qualify, link table as appropriate.
• Reduce synthetic keys and loops.
• Avoid using count distinct.
• Avoid using calculated dimensions.
• If date column contains the time information and time information is not required, remove the time information by using floor() function.
• Perform incremental load to load only new and updated data in the tables.

Question.15 Does Set Analysis occurs always in QlikView expression?

Answer: Yes. Set Analysis always occurs in QlikView expressions. For e.g., When Sum (Amount) is used in an expression, it is actually executing Sum ({$) Sales) $ is by default for current selection and is optional.

Question.16 There are 10 users and they want to see data only pertaining to them. How you will achieve this. You will create 10 dashboards or one dashboard?

Answer: This will be done by creating one dashboard, but assigning security to users based on Section Access.

Question.17 What best practices should be followed while creating a dashboard?

Answer: While creating a dashboard, care should be given so that the dashboard is clean and easy
to understand. Following practices can be followed

• Design dashboard for a specific Screen resolution. Discuss with your user community and decide on a screen resolution that will cater to all the users.
• Design a Screen layout which makes the navigation on the screen natural and easy. The basic structure is list boxes on the left. Time related list boxes on the top center. Charts and tables in the middle of the screen.
• Avoid using complex calculations in the dashboard. Move such calculations to the
  script.
• Use muted colors. So that focus is in the dashboard not on the color.
• Create a template and include all the layout related attributes on this template. Use this template to develop the dashboards.

Question.18 What are the responsibilities of a QlikView professional?

Answer: QlikView consultant or developer’s responsibilities may differ based on specific organization, but at high-level it consists of

• Understanding the requirements.
• Extracting data and creating a data model by applying required transformations.
• Creating dashboards by using different objects such as charts, text boxes etc. for
  data analysis.
• Deploying the dashboards on the server.

Question.19 How you will gain an understanding of an already developed QlikView application?

Answer: To understand an existing application,

• See what data elements, objects, sheets are displayed on the dashboard.
• Use System fields to understand the data loaded in the dashboard. System fields are prefixed by $ and can be used to create list box.
• Variable overview and Expression overview will give details on the variables and expression used in the application.
• Settings/Document settings will give details on the sheets used. It will also show details on the hidden sheets.
• Document settings will also provide details on different sheet objects, groups, triggers etc. used in the development.
• A look at the Table Viewer will show the tables loaded and relationship between them.
• To understand scripts, invoke the script editor and review each tab. Execute only one tab and comment other tabs. Load one table at a time.