1. What is TABLEAU? Tableau is the powerful and fastest visualizing tool that is used in the Business Intelligence(BI) Industry. It simplifies the raw data into an understandable format. Analysis of the data becomes faster with Tableau. The visualizations can be created in the form of dashboards. The visualizations or diagrammatic representation of data can easily be understood by the employees of the organizations who are at different levels. 2. What is data visualization? Data visualization means the graphical representation of data or information. We can use visual objects like graphs, charts, bars, and a lot more. Data visualization tools provide an accessible way to see and understand the data easily. 3. List out Tableau File Extensions. The below ones are few extensions in Tableau: • Tableau Workbook (.twb) • Tableau Data extract (.tde) • Tableau Datasource (.tds) • Tableau Packaged Datasource (.tdsx) • Tableau Bookmark (.tbm) • Tableau Map Source (.tms) • Tableau Packaged Workbook (.twbx) – zip file containing .twb and external files. • Tableau Preferences (.tps). 4. What is the latest version of Tableau Desktop? Tableau Desktop's latest version is 2021.3(as of, 7thSep 2021). 5. Define Heat Map? A heat map is a graphical representation of data that uses the color-coding technique to represent different values of data. As the marks heat up due to their higher value, dark colors will be shown on the map. 6. Define TreeMap? TreeMap is a visualization that organizes data hierarchically and shows them as a set of nested rectangles. The size and colors of rectangles are respective to the values of the data points they project. Parent rectangles will be tiled with their child elements. 7. What is the difference between a Heat map and Treemap? TreeMap Heat MapIt represents the data hierarchically and shows them as a set of nested rectangles. It represents the data graphically which uses multiple colors to represent different values. It is used for comparing the categories with colors, size, and it can also be used for illustrating the hierarchical data and part to whole relationships. It is used for comparing the categories based on color and size. And also it is great in spotting the patterns based on the density of the information. The colors and size of rectangles are respective to the values of the data points When their values are higher or density of records, the data will represent in dark color. 8. What are the different data types in Tableau? Tableau supports below data types.Data TypeMeaningExamplesStringCharacter Sequence. Enclosed in ''.Tableau', 'World'Number (Whole)Integers9Number (decimal)Floating values.123.45BooleanThey are logical values.TRUE, FALSEDateDate"02/01/2015"Date & TimeDate and Time01 January 2019 05:55:00 PMGeographic ValuesGeographical ValuesIndia, Italy, Canada 9. Give a brief about the tableau dashboard? Tableau dashboard is a group of various views which allows you to compare different types of data simultaneously. Datasheets and dashboards are connected if any modification happens to the data that directly reflects in dashboards. It is the most efficient approach to visualize the data and analyze it. 10. Define Page Shelf in Tableau? Page shelf breaks the views into a series of pages. It displays an alternate view on each page. Due to this feature, you can analyze the effect of each field on the rest of the data in the view. 11. Define the story in Tableau? The story can be defined as a sheet which is a collection of series of worksheets and dashboards used to convey the insights of data. A story can be used to show the connection between facts and outcomes that impacts the decision-making process. A story can be published on the web or can be presented to the audience. 12. Give an overview of the fact and dimensions of the table? Facts are numeric measures of data. They are stored in fact tables. Fact tables store that type of data that will be analyzed by dimension tables. Fact tables have foreign keys associating with dimension tables. Dimensions are descriptive attributes of data. Those will be stored in the dimensions table. For example, customer’s information like name, number, and email will be stored in the dimension table. 13. State some ways to improve the performance of Tableau • Use an Extract to make workbooks run faster • Reduce the scope of data to decrease the volume of data • Reduce the number of marks on the view to avoid information overload • Try to use integers or Booleans in calculations as they are much faster than strings • Hide unused fields • Use Context filters • Reduce filter usage and use some alternative way to achieve the same result • Use indexing in tables and use the same fields for filtering • Remove unnecessary calculations and sheets 14. Explain different connection types in Tableau? There are 2 connection types available in Tableau. Extract: Extract is a snapshot of data that will be extracted from the data source and put into the Tableau repository. This snapshot can be refreshed periodically fully or incrementally. This can be scheduled in Tableau Server. Live: It creates a direct connection to the data source and data will be fetched directly from tables. So, data will be up to date and consistent. But, this also affects access speed. 15. Define a Histogram chart? A histogram chart shows the distribution of continuous information over a certain period of time. This chart helps us to find extreme points, gaps, unusual values, and more concentrated values. 16. What are the file size limitations with Tableau? In Tableau, there are no limitations with the file sizes. And moreover, there is no row or column limit to import the data. 17. What is a Column chart? A column chat visualizes the data as a set of rectangle columns, as their lengths are proportional to values when they represent the data. The horizontal axis shows the category to which they belong, and the vertical axis shows the values. 18. What is the Bar Chart in Tableau? The bar chart visualizes the data as a set of rectangle bars, as their values are proportional to lengths when they represent the data. The vertical axis shows the category to which they belong to and the horizontal axis shows the values. So, the bar chart is a vertical version of the Column chart. 19. What is the Line Chart? The line chart is a popular type of diagrammatic way for visualizing the data, it connects the individual data points to view the data. We can easily visualize the series of values, we can see trends over time or predict future values. The horizontal axis holds the category to which it belongs and the vertical axis holds the values. 20. What is a Stacked Bar chart? Stacked Bar Chart, composed of multiple bars stacked horizontally, one below the other. The length of the bar depends on the value in the data point. A stacked bar chart makes the work easier, they will help us to know the changes in all variables presented, side by side. We can watch the changes in their total and forecast future values. 21. What is a Stacked Column Chart? Stacked Column Chart, composed of multiple bars stacked vertically, one on another. The length of the bar depends on the value in the data point. A stacked column chart is the best one to know the changes in all variables. This type of chart should be checked when the number of series is higher than two. 22. What is an Area Chart? An area chart is nothing but line chat, the area between the x-axis and lines will be color or patterns. These charts are typically used to represent accumulated totals over time and are the conventional way to display stacked lines. 23. What are the products offered by Tableau? Explain a few things about them. Tableau has 4 main products.  Tableau Prep: Tableau Prep is responsible for preparing data for analysis. This tool provides 3 coordinated views which provide us with a complete picture of data.  Tableau Desktop: Tableau Desktop is the place where the analysis happens. It has powerful drag and drops analytics which is very easy to use. Through the desktop, you get your data insights quickly.  Tableau Online: Tableau Online is a secure and scalable self-service analytics cloud tool. You can use it anywhere, anytime and it has eliminated the complexities of IT.  Tableau Server: From small to large enterprises, Tableau server is used for fulfilling their BI requirements. This is an on-premise solution. This tool can take data from anywhere and shared it across the organization through the desktop or mobile browsers. 24. Explain how many types of filters are available in Tableau? Filters are used to provide the correct information to viewers after removing unnecessary data. There are various types of filters available in Tableau.  Extract Filters – Extract filters are used to apply filters on extracted data from the data source. For this filter, data is extracted from the data source and placed into the Tableau data repository.  Datasource Filters – Datasource filters are the same as extract filters. They also work on the extracted dataset. But, the only difference is it works with both live and extract connections.  Context Filters – Context Filters are applied on the data rows before any other filters. They are limited to views, but they can be applied on selected sheets. They define Aggregation and Disaggregation of data in Tableau  Dimension Filters – Dimension filters are used to apply filters on dimensions in worksheets. Dimension filters are applied through the top or bottom conditions, formula, and wildcard match.  Measure Filters – Measure filters are applied to the values present in the measures. 25. Differentiate between Tiled and Floating in dashboards? In a tiled layout, items don’t overlap. The layout will be adjusted according to dashboard size. In the floating layout, items can be placed on some other layers. Floating items can have fixed positions and sizes. 26. What is the difference between .twb and .twbx extensions? .twb: .twb means Tableau workbook. .twb is an XML sheet, it stores the data about your documents, stories, and dashboards. This file is the reference to the source file such as Excel or tde. This file will be linked to your source file when you save the TWB file. If you want to share your workbook you need to send both the workbook and data source file. .twbx: It is a compressed file, where you have all files. It includes data source files, twb, and other files to produce the workbook. TWBX is obsolete for sharing because it will share the copy of the file instead of an original source file. .twbx is used for reports and we can view using the tableau viewer. 27. Why Tableau? • Tableau is very simple and user-friendly. • Tableau helps in analyzing the data and using this one can change the raw data into an understandable format. • Users can blend the data with the other data to create their own views on the data and to share it with the customers, and colleagues. • Users can manage a large amount of data. • It can easily integrate with multiple data sources. • Tableau can create complex graphs which simply look like pivot table graphs in Excel. • It gives quick calculations on datasets. • Users can create the visuals easily and switch between the types, to find the model to represent the user messages. 28. State some reasons for the low performance of Tableau? Explain in detail. Following are the reason for low performance • Filters - filters need to create an extra query and if it used in large numbers and inefficiently then they can reduce the performance. So, it is advised to use filters whenever it is mandatory • Live connection - Tableau extract works much better in comparison with a live connection. • Data sources - a wrong query to a wrong data source can reduce performance. Also, the data source’s performance can also affect Tableau’s performance. 29. State some ways to improve the performance of Tableau. Following are the few ways to improve the performance • Use an Extract to make workbooks run faster • Reduce the scope of data to decrease the volume of data • Reduce the number of marks on the view to avoid information overload • Try to use integers or Booleans in calculations as they are much faster than strings • Hide unused fields • Use Context filters • Reduce filter usage and use some alternative way to achieve the same result • Use indexing in tables and use the same fields for filtering • Remove unnecessary calculations and sheets. 30. Which one is better? Extract or Live connection? Extract connection is better than live connection because extract connection can be used from anywhere, anytime without connecting to the database. We can construct our own visualizations on it irrespective of the database connection.