QlikView Interview Questions and Answers for Updates
QlikView Interview Questions will be very helpful for the beginners and also for experienced candidates.
1. What chart types do we use in QlikView Admin?
Ans: In QlikView Admin, we generally use bar charts, line charts, combo charts, scatter charts, grid charts, etc.
2. What are the features of the QlikView?
Ans: QlikView helps to create various kinds of reports from various data sources that help the company to demonstrate various topics.
Automatically Data association creation: It automatically recognizes the relationship between each piece of data stored in the dataset. Users do not need to reconfigure the relationship between different data entities.
Date held into fast memory: It stores the structure of the data for various users in RAM for fast user experience which makes it the most attractive platform compared to other available platforms.
Aggregations are calculated on the fly as needed. It stores the data in memory, calculations are done on the fly. So there is no need of storing pre-calculated aggregate values.
Relationship visualization by color: Relationship among data is not shown by arrow or lines but by different colors. Selecting a piece of data gives instant colors to the related data and another color to unrelated data.
Direct and Indirect searches: It provides the features to search the data in both ways direct and indirect way because of the association between the data. Instead of giving the direct value a user is looking for, a user can give some related data and get the exact result because of the data association.
Data is compressed to 10% of its original size: It heavily uses the data dictionary. Only mandatory bits of data in memory are required for any analysis. Therefore, it compresses the original data into small size.
3. Explain Qlikview architecture?
Ans: QlikView deployments have three main infrastructure
1. QlikView Developer: it is a Windows-based desktop tool which is used by designers and developers to create
- a data extract and transformation model and
- to create the graphical user interface.
2. QlikView Server (QVS): It Handles the communication between clients and the QlikView applications. It loads QlikView applications into memory and calculates the presents user selections in real time.
3. QlikView Publisher: It Loads data from various data sources (oledb/odbc, xml, xls), reduces the QlikView application and distributes to a QVS.
Because of QlikView Server and Publisher has various roles and handle CPU and memory differently it considered a best practice to separate these two components on differeant servers.
4. What are the benefits of using QlikView?
Ans: As the name suggests, QlikView is a combination of ‘quick’ and ‘click,’ and its features make it intuitive and easy to use. Users can visualize data, search in multiple datasets, create ad-hoc reports, and view patterns and trends in data that may not be visible in other reports.
- Flexible: Dashboards are web-based and accessible from desktop computers and mobile devices.
- Interactive: Users are able to easily drill down and select particular information from charts or tables.
- Usable: Users can see large amounts of data effectively and essentially.
- Scalable: QlikView is useful for different business processes at analytical, operational, and strategic levels.
5. What is Resident Load?
Ans: Occupant stack is a piece of stacking data in Qlikview application. It is used for stacking information in tables which is as of now stacked in Qlikview application.
6. What do you understand by layers in QlikView?
Ans: Layers are basically set on sheet object properties in the layout tab, where there are options such as Bottom, Top, and Normal, respective to the numbers −1, 0, and 1.
7. What are Circular loops in QlikView?
Ans: A circular loop is created when the relationship between two tables can be established both directly and through another third table.
8. What is a hidden script in QlikView?
Ans: A Hidden script is a part of the script that executes before the execution of normal script and it is protected by a password.
9. What are the different types of tables in QlikView?
Ans: There are different types of tables which can use to represent data in a tabular structure. The types of tables available in QlikView are; Straight table, Pivot table, Mapping table, Cross table and a simple table sheet object.
10. Explain About Normalized Data?
Ans: Well Structured Form of Data, it doesn’t have any repetition or redundancy of data. It is a kind of Relational data. It is mainly used in OLTP kind of stuffs Denormalized Data –It is a bunch of data without any relationship among themselves, with redundancy of data. It’s mainly used in OLAP kind of stuffs.
11. What are QlikView Annotations?
Ans: collaboration object, QlikView users can engage in threaded discussions with the QlikView content. A user can create notes linked with any QlikView object. Other users can then add their own commentary to create a threaded discussion.
Users can capture snapshots of their selections and include them in the discussion so that others can get back to the same place in the analysis when reviewing notes and comments. Also, QlikView captures the position of the object as well as knows who has made each note and comment and when and how a decision was made.
12. How can we connect to a database from the script editor?
Ans: At the bottom half of the script editor, a section named Database is present. We can connect to a database by the selecting the connection method from ODBC or OLE DB and then clicking on Connect. Then, we have to select a Data Source Name (DSN) from the list of databases available and that database will be connected to QlikView.
13. Explain Set Analysis in QlikView?
Ans: Mostly used in aggregated functions like sum (year), avg, max, min, etc., set analysis is used to define a set (or a group) of data values.
14. What Are The Requirements For Installing Qlikview?
Ans: The QlikView installation package uses Windows installer technique and you must have version 2.0 or higher running on your system. If the package isn’t deployed by a system administrator with a deployment tool, the account that is to run the installation must have administrator privileges.
15. Differentiate Between Set And Let Option In Qlikview?
Ans: Set: it assigns the variable without assesses the expression.
Let: it assigns the variable with assesses the expression.
16. Explain the Difference between Straight table and pivot table?
Ans: This is the basic QlikView Interview Question asked in an interview. A straight table is better in sorting than a Pivot table. We can sort it according to any columns. It is not good in the grouping. Subtotals are not possible in the Straight table.
While in the pivot table is very good in grouping we can easily see which group a specific row belongs to, and a group can have a subtotal also. But when you sort a pivot table, we have to sort it first according to the 1st dimension, then according to the next. we can display a pivot table like a cross table, pivot table does not support the sorting.
17. What is Left Join?
Ans: Left join specifies that the join between two tables should be left join; it uses before the word ‘join’. The resulting table only contains the combination among two tables with the full dataset from the first table. When we have more than one common field between two or more tables, then we have synthetic keys.
18. What is a Bookmark in QlikView?
Ans: A bookmark in QlikView captures the selections in all states defined in a QlikView document. It can be saved and accessed later.
19. Clarify the confinements of Binary load for a QlikView Developer?
Ans: Parallel Load can be used for a single application implies we can just persue the information from one QVW application and additionally set contents is likewise a confinement.
20. What are the different types of data load?
Ans: There are seven different types of load in QlikView.
- Load from files
- Resident Load
- Incremental Load
- Inline Load
- Add Load
- Buffer Load
- Binary Load
21. How many types of charts can be created in QlikView?
Ans: There are total 13 types of charts in QlikView and their names are;
Bar chart, Line chart, Combo Chart, Scatter Chart, Mekko Chart, Gauge chart, Pie chart, Funnel chart, Radar chart, Block chart, Grid chart, Straight table chart and Pivot table chart.
22. Discuss one scenario where you can use Rank() function?
Ans: Let us suppose that a car company wants to know the performance of countries in sales. For this, they would want to rank the countries based on sales occurred in them. For this we will use Rank() function on the total of sales amount for each country. The expression would look something like this, Rank(sum(Sales_in_country)). This would rank the countries from highest to lowest based on total sales value for each. If Australia had sales of 10,00,000 it will rank 1st. Then if the USA had sales of 9,80,000 then it will rank 2nd and so on.
23. What is a Star Schema?
Ans: A star schema is a way of representing a data model which has a central fact table to which individual dimension tables link. It is a relational database model which shows a multi-dimensional database. It named as a star schema because the entire relationship diagram of the fact table and dimension table looks like a star.
24. What operations can you consider using the Tools menu given in the Menu bar?
Ans: In the Tools menu we can use the Edit Menu to edit the tools, make different kinds of charts using wizards like Quick Chart Wizard, Time Chart Wizard, Statistics Chart Wizard and Box Plot Wizard. Two other tasks can be improved through this menu which are Alerts and Themes making.
25. What do you mean by Buffer load? How is it Significant?
Ans: A buffer load statement is used to transform a file into QVD file or create and maintain a file as QVD in QlikView’s memory for future use. Such files are created using a Buffer prefix and is typically stored in the user defined location selected through User Preferences > Locations.
26. Mention the difference between a list box and a multi box?
Ans: A list box displays all the values of a single table field in the form of a list. It is used to make selections of data values convenient. Whereas, a multi-box is a compressed table showing only the fields on display. You need to click on the Add sign to view data values of each field. So, the main difference between the two is that in list box you can only get one field displayed but in a multi-box all the fields can display.
27. What Is Windows Installer?
Ans: The Windows installer is standard developed by Microsoft for software installation, modification, repair and removal. The installation package, also known as the msi, comprises of a database and the files to be installed
28. What is the difference between Keep, Join and Concatenate?
Ans: This is the general QlikView interview question asked in an interview. In case of keep both the datasets are available in QlikView’s memory while in the case of the join the load statements produce only one dataset from which you have to choose the columns. There is no concept of the outer keep whereas we have outer join available in case of joins. Join gives the result from two tables as records containing columns form both tables. But Concatenate only appends the rows from one table to another.
29. Define Trellis char?
Ans: In the trellis chart, we can create an array of charts based on the first dimension. It is generally a grid of small charts or a repetition of charts. Bitmap charts can also be made up of the trellis display.
30. Mention The Differences Between Pivot Tables And Straight Tables?
Ans: Pivot data is grouped. Partial sums can be shown in pivot tables, but not straight.
31. Can The Installation Overwrite Important System Files?
Ans: No, the overwriting of files is handled by the Windows installer service itself which uses the Windows File Protection rules.
32. Deacribe the Synthetic key and how to avoid it in QlikView?
Ans: In QlikView data structure, it is undesirable to have multiple common keys across multiple tables. Due to this QlikView may use the complex
keys Synthetic key to generate the connections in the data structure. Synthetic keys use a heavy resource and may slow down calculations, in extreme cases, degrade the performance of the applications. This key also makes a document difficult to understand and maintain. There are some scenarios where synthetic keys cannot be avoided (Example- Interval Match tables), but, in general, synthetic keys should always be removed, if it is possible to comment the fields in load scripts rename the fields using UNQUALIFY operator.
33. What do you know about associative nature of data in QlikView?
Ans: By associative nature of data, it is meant that all the fields and data field values are associated with each other (the ones loaded in the same document). For example, if there is a table on country wise sales, it is related to sales in QlikView document .Then when we select a country, say India, from a column in the table, data values related or linked to sales in India will get filtered by the system. All the other, unrelated/irrelevant information will be deactivated or sorted out.
34. Can we load Web files into QlikView? If yes, how?
Ans: Yes, we can load web files into QlikView. It is done through the Script Editor wherein the Data tab an option of ‘Web Files’ is given. select the option and will ask for the URL of the web file and the file can be loaded.
35. How can you handle Early Arriving Facts?
Ans: We can load data from ODBC, OLEDB, or SAP connectors with the help of the select statement, and we can load files like Excel, Word, etc. by using the table syntax.
36. What the mobile device platforms does QlikView 11 support?
Ans: QlikView 11 delivers mobile are the functionality for Apple iOS and Android tablets and smartphones. QlikView supports Android tablets when the following given conditions are met:
- QlikView Server 10 SR3 or later versions
- A native browser, not a downloaded one
- Currently, HTML5 web apps support only Apple and Android handhelds because BlackBerry devices are older that do not fully support HTML5 (and many of them are having non-touch screens). QlikView doesn’t have a web-based solution for them as of now.
37.Name the types of files you can load data from?
Ans: In the Load from files type of load, data can be loaded using several different file types. These files are, Excel files(xls), Dif files, Xml, Kml files, CSV files, web files (html), Qvd and Qvx.
38.What are Sheets in QlikView?
Ans: Sheets divide a QlikView document into several sections. Every document will have at least one sheet and that is named ‘Main’, you can add more if you want and edit their properties from the Sheet Properties option.
39. What do you understand by Kurtosis() and Skew() functions?
Ans: Kurtosis() and Skew() are a type of statistical aggregate functions. Kurtosis() measures the peak of a frequency distribution curve. anyway, Skew() measures the symmetry in a statistical distribution curve.
40. What does the Unwrap function do?
Ans: The Unwrap function undo the operations performed by the Wrap function. The wrap function takes the bottom half of a table and puts it adjacent (on the right section) of the first half. Whereas, the unwrap function takes this right section of the table and puts it back below the upper section of the table.
41. How Does Qlikview Stores The Data Internally?
Ans: Qlikview stores the information in QVD as QVD. it has data compression capability. Qlikview has better performance than other BI because of having its memory analytics approach.
42. Explain Joins And Its Types?
Ans: Joins is used to convert the given data, whenever we are using joins for converting data. it is known ad Data Merging.
these are many types:
- Left join
- Right join
- Inner join, etc
43. Differentiate Between Qv Server And Publisher?
Ans: QV Server is a program that is installed on computer with many CALS which allows user to access QV Files on the server. Publisher is a program. it manages the centralized control on our QV files and manages them how and when they are loaded and distributed.
44. distinguish Between key Qlikview And Any Other Standard Statistical Software Package (sas, Spss)?
Ans: Key varaiation is in the terms of the database used. QlikView offers a quite simple visualization that similar to MS excel filtering. SAS is useful in case of Meta data even SPSS is good for analysis.
- In variance of the above three, QlikView is most user friendly and fast in terms of generating diverse dashboards/templates.
- In the terms of calculations, advanced statistics options are limited in QlikView.
- For market research and analysis SPSS contains direct facility algorithms.
45. What are Sheet Objects? Name them?
Ans: Sheet Objects are the items that displays data in a certain way for the user. A dashboard is made using these sheet objects appropriately. These are many types of sheet objects available like,
- List box
- Statistics box
- Table box
- Input box
- Current Selection box
- Text Object.
46. Name the 6 different types of Aggregate functions?
Ans: Six types or categories of aggregate functions are; Basic, String, Counter, Advanced, Statistical and Financial Aggregate Functions.
47. What is Pivot table?
Ans: A pivot table is better for the time of grouping. We can also show a pivot table like a cross table, it is a beneficial feature. However, there is a disadvantage with pivot tables, i.e., if we have to sort a pivot table, then we have to sort it first according to the first dimension, then to the next.
48. What is Inner Join?
Ans: The join and keep prefixes in the QlikView script language and it can be preceded by the prefix inner. If used before joining, it specifies that the join between the two tables should be an inner join. The resulting table contains only combinations between the two tables with a full of information set from both sides. If used before keep, it consider that the two tables should be reduced to their common intersection before being stored in QlikView.
49. What is a selection indicator in QlikView Document?
Ans: A selection indicator is used to represents the type of association between the data present in different sheet objects. A green dot shows selected values, blue dot indicates locked values and red dot indicates de-selected values in AND mode.
50. Clarify Set examination in Qlikview?
Ans: It is used for set of collections. it is necessary for the most part which is utilized in collected capacity like total (year), and so forth. Experience this keen blog to realize why this QlikView is such an extraordinary Business Intelligence instrument.