Successful businesses forecast, make decisions and develop strategies based on data. Tableau is a data-driven tool used for data interpretation.

Importance of Tableau as a BI and visualization tool

One of the most well-liked business intelligence (BI) and visualization solutions available today is Tableau. It gives users the option to visualize data in several ways and can be used to discover patterns and trends.

business-intelligence-BI

It can be applied to gather data, analyze it, and reach conclusions. It is adaptable and applicable to many different sectors for more complex analytics.

It enables users to produce and distribute interactive maps and dashboards to understand their data better. Developers and administrators can utilize Tableau to create in-depth reports and visual data representations.

Tableau is a flexible tool that both small and large enterprises can utilize. Due to its widespread use has a lot of potential for use in various industries, including marketing, finance, and human resources.

Most often asked Tableau interview questions and their responses.

What is data visualization?

Answer: Data visualization is the presentation of data in a graphical or pictorial format. It is often used to explore and understand data, find patterns and relationships, and communicate findings. Users can use data visualization to represent many data types, including numerical, categorical, and temporal data.

What is Tableau?

Answer: Tableau is a powerful visualization tool. It can visualize data in any format, including reports, graphs, maps, and data visualizations. Tableau can be used to understand trends and make informed decisions. It is utilized globally by business experts and data analysts to make data-driven judgments.

What Are the Data Types Supported in Tableau?

Answer: Several data types can be used in Tableau, making data analysis and visualization much more effortless. These data types include text, numbers, dates, times, boolean values, clusters, and maps.

What are the advantages of using Tableau?

Answer: Tableau offers a wide range of advantages, such as

  • Interactive Data visualization
  • Ease of implementation
  • Easily handles large amounts of data
  • Mobile support & responsive dashboard
  • High performance
  • Interpret geodata
  • Combines charts
  • Flexibility
  • Ability to use other scripting languages

What are the different Tableau Products, and what is the latest version of Tableau?

Answer: The latest version of Tableau is 2022.2

Tableau offers five main products:

  • Desktop
  • Cloud
  • Server
  • Data Preparation
  • Data Management

Additional products are:

  • CRM
  • Embedded Analytics
  • Public
  • Mobile
  • Reader
  • Bridge

What is a parameter in Tableau?

Answer: In Tableau, parameters are used to control the behavior of worksheets and reports. Tableau parameters can be specified in various ways, including using Tableau’s embeddable parameter boxes, text fields, and calculation fields. Tableau also supports external references to parameters from other sources.

Tell me different ways to use parameters in Tableau

Answer: Tableau parameters are a robust tool that may be applied in numerous ways to produce the desired results. Using these, you may determine how the data will be displayed, filter and sort the data, and personalize the data visualizations.

In other words, There are four typical uses for parameters. Filters, bins, reference lines, and computed fields are among them.

What are continuous and discrete field types?

Answer: In Tableau, fields can be either continuous or discrete. Continuous fields are quantitative values that can be added, subtracted, and averaged. Examples of continuous data include Sales, Profit, and Quantity.

Discrete fields are quantitative values that can be counted but not added, subtracted, or averaged.

What is Tableau Server?

Answer: You can use the Tableau server to host and administer workbooks, reports, dashboards, and data sources created with Tableau Desktop.

Tableau Server can be installed on a Windows or Linux server. Users can access Tableau Server via a browser to build new workspaces, publish reports and dashboards, and share them with other users.

What are data extract files in Tableau?

Answer: Data extracts are saved subsets of data you can utilize to enhance performance or benefit from Tableau features that aren’t supported or available in your original data.

You can use filters and other limitations to lower the overall amount of data when creating an extract of your data.

What is a Tableau Dashboard?

Answer: Tableau Dashboards are a fantastic method to present complex data sets in a simple way to understand. Tableau Dashboards can offer insights that might otherwise be challenging to gain from raw data by combining charts, graphs, and tables.

Users can quickly create and share dynamic data representations using a Tableau Dashboard for data visualization.

State the components of Tableau Architecture

Answer: Primarily, there are five components in Tableau Architecture

1. Data Server: The main component of Tableau Architecture

2. Data Connector: Acts as an interface between Data Sources and Data Servers

3. Components: Application Server, VizQL Server, Data Server

4. Gateway: Handles processes like URL Rewriting, Load Balancer, etc

5. Clients: Tableau Desktop, mobile applications, web browser

What is the difference between published data and embedded data sources in Tableau?

Answer: Tableau supports both public and embedded data sources. While embedded data sources are saved in a workbook, published data sources are saved on Tableau Server or Tableau Online.

Published data sources can connect to various users, whereas embedded data sources can only be used by the person who produced them. The embedded data sources require a separate refresh schedule, while published data sources require a single refresh schedule.

What is Tableau Reader?

Answer: Tableau Reader is a data visualization and analysis software that helps users explore, understand, and act on data. It is designed to be easy to use, regardless of experience level.

Tableau Reader provides various data exploration, analysis, and presentation tools, making it a powerful tool for data scientists, business analysts, and information professionals.

What are Filters? How many types of Filters are there in Tableau?

Answer: The act of filtering involves deleting a specific value or range of values from a result set. The Tableau filtering function supports simple field value scenarios and complex calculations or context-based filters.

Types of Filters: Extract filters, data source filters, context filters, dimension filters, and measure filters.

What are the different types of joins in Tableau?

Answer: Tableau supports four types of joins: Inner Join, Left Join, Right Join, and Full Outer Join. It can link up to 32 tables in a single data source.

What is the Difference between Joining and Blending?

Answer: Joining and blending data in a Tableau represent different ways of connecting the data in your analysis.

Joining data means adding the data together while blending means taking the data from one table and combining it with data from another table.

Joining is the default action when you connect data in Tableau, but blending can be more efficient if you want to change the data before you analyze it.

What is the difference between a Heatmap and a TreeMap?

Answer: Heatmaps and TreeMaps are both visualizations in Tableau that are used to compare data. Heatmaps use color to show how data points are related, while TreeMaps use size and color to show how data points are associated.

Heatmaps are best used when you have many data points and want to find patterns. TreeMaps are best used when you have a smaller number of data points and want to show the data hierarchy.

What is the difference between shared axis charts, combined axis charts, and dual axis charts?

Answer: When creating visualizations in Tableau, there are three main chart types to choose from: the shared axis chart, the combined axis chart, and the dual axis chart. They differ regarding how data is displayed, and axes are linked.

A shared axis chart, also known as a simplex chart, is a type of chart that is used to show relationships between two dimensions. It is simple to create and easy to understand

A combined axis chart combines the features of a bar and line chart. It displays data on two axes and the relationship between items on the axes.

Dual axis charts show the relationship between two sets of data.

What is the difference between twb and twbx file extensions?

Answer: The metadata for a Tableau workbook is stored in an XML file known as a Tableau workbook (.twb). It includes the worksheets, the data source connection information, and the workbook’s layout and format.

A packed file called a Tableau packaged workbook (.twbx) contains the workbook XML and any external files required to support its data sources.

What are the different types of functions generally used in Tableau?

Answer: Tableau offers a wide variety of functions for usage in Tableau calculations.

  • Number Functions
  • String Functions
  • Date Functions
  • Logical Functions
  • Aggregate Functions
  • User Functions
  • Table Calculations
  • Spatial Functions
  • Additional Functions

What is the story in Tableau?

Answer: A story is a series of visuals that function as one to convey information. Stories can support ideas by clarifying how facts relate to one another and how decisions impact outcomes.

Explain different connection types in Tableau.

Answer: Tableau can connect to all the popular data sources which are widely used, such as:

  • Text files: MS Excel, PDFs, JSON, Access, 
  • Databases: Tableau server, MySQL, DB2, Oracle, SQL Server, PostgreSQL, Redshift
  • Cloud: Microsoft Azure, Google BigQuery, Salesforce
  • Other Sources using ODBC
  • Connection to websites through a web data connector

The following are more data connection types that Tableau supports.

connectiontypesin-tableau
Image credit: theinformationlab.co.uk

What is a Page shelf?

Answer: In Tableau, a page shelf is a tool for data organization. They’re like folders in a file system, and you can group them by topic or date. They are ideal for arranging complex data.

It can also be defined as – To properly understand how a particular field affects the other data in a view, a Page shelf enables you to divide a view into several pages.

What is the RANK Function in Tableau?

Answer: Tableau’s RANK function is a helpful feature that lets you order the numbers in a data set. This function is used to rank values in a data collection to one another or to determine the top or bottom values in a data set.

In other words, the Rank function, as the name suggests, is used to give the rank to any measure (number related) included in the data set. For instance, the highest value is ranked highest, and the lowest is ranked lowest.

What is the difference between INDEX and RANK in Tableau?

Answer: Tableau provides two methods for sorting your data: INDEX and RANK.

INDEX sorts data by a numerical value, while RANK sorts data by rank.

The INDEX primarily deals with the record’s physical location, and incremental numbers are assigned based on the records’ physical order.

For example:

ExpenseIndex
20001
60002
70003
10004

RANK primarily concerns the record’s value, which means records with higher values are ranked higher, and records with lower values are ranked lower.

For example:

ExpenseRank
20003
60002
70001
10004

What are some limitations of Tableau?

Answer: The following are the limitations of Tableau:

  • Tableau can only work with cleaned data and focuses primarily on visualization.
  • Lacks data modeling and data dictionary capabilities for data analysts.
  • When developing data logic and dashboards, there is a lack of version control and collaboration.
  • Tableau does not offer the option of using scheduling to refresh reports automatically.
  • Developers must produce fresh visuals rather than import them.
  • Supports only a 16-column table with limited formatting
  • The parameters cannot be updated automatically; manual action is necessary.
  • Dashboards are not responsive, so the developer needs to design a separate dashboard for mobile and desktop.
  • Scaling this product across a big company is highly expensive. Compared to BI tools that are more affordable and complete.

How is Tableau different from other BI tools?

Answer: The primary difference between the two is that Tableau has a far more user-friendly and intuitive interface than other business intelligence systems. Unlike other programs that may require a certain amount of technical knowledge and understanding, anyone with a basic grasp of computers can learn and use Tableau.

It also has a more incredible tool selection that lets users create more complex visualizations. It is also noticeably more flexible and adaptable than its competitors, allowing users to make incredibly unique and customized representations.

Its emphasis is primarily on visual analysis than on data manipulation. Hence developers can quickly access and understand massive amounts of data.

How Can You Optimize the Performance of a Dashboard?

Answer: Tableau dashboards are designed to present data in a form that is simple to understand. Developers can enhance a dashboard’s performance to ensure the data is displayed accurately and promptly.

There are a few ways to optimize the performance of a dashboard.

  • Using appropriate data management methods, such as optimizing extracts and minimizing the number of fields and records.
  • Instead of viewing everything in one view, group related views together and connect them with action filters.
  • Avoid using too many filters because this will make your query more complex and take longer to produce results.
  • Use the query optimization in Tableau.
  • To reduce overhead in Tableau, lessen the number of nested computations and perform calculations wherever possible in the database.
  • Cut back on extra worksheets, get rid of unused worksheets, etc.
  • Reduce the number of blends and minimize joined tables.

What is Quick Sorting in Tableau?

Answer: Quick Sorting in Tableau is a method that helps you rearrange the order of data in your worksheet. Quick Sorting is a built-in feature of Tableau that you can use to sort your data in ascending or descending order.

To use Quick Sorting, select the data you want to sort and click on the sort button in the toolbar. You can also use the keyboard shortcut Alt + Shift + S to sort your data.

What is a Tableau worksheet?

Answer: A Tableau worksheet is an interactive data visualization that allows you to explore, work with, and understand your data. A worksheet can contain one or more visualization objects, such as charts, tables, maps, and images.

You can use worksheets to answer questions, analyze, and tell stories with your data. Worksheets are the foundation of a Tableau workbook.

What is the difference between the quick and normal filters in Tableau?

Answer: Quick filters in Tableau are more efficient than normal filters. The difference is that normal filters restrict the view data to just what is in the cells, whereas quick filters can extract data from a column that is not in the cells.

The quick filter is more efficient because it doesn’t need to go through the whole table to find the data it needs.