Learning Tableau is the key to uncovering a wealth of insights about the data visualisation world. Envision yourself starting an interview full of confidence and prepared to answer questions about anything from developing calculated fields to maximising dashboard performance. This blog will examine a few common Tableau Interview Questions and offer suggestions for giving compelling responses. Enrolling in a Business Intelligence Course can help you succeed in this venture by improving your abilities and gaining a better understanding.
What is Tableau?
Tableau is a business intelligence tool that works on data to transform them from their raw nature to comprehensible layouts using tools like bars, lines, pie charts, and dashboards. It enables the creation of intelligent and collaborative data dashboards. Users are also provided with the means to visualise data trends, variation, or density in the form of graphs and charts. Tableau can import relational and big data files to collect and analyse data.
What Different Products Does Tableau Offer
Tableau provides several products that address various facets of data analysis and visualisation: ⦁ Tableau Desktop: Enables users to create and share dashboards independently. ⦁ Tableau Server: For sharing dashboards throughout an organisation while maintaining security and control. ⦁ Tableau Online: A cloud based dashboard sharing platform. ⦁ Tableau Prep: A data preparation, cleaning, and shaping tool. ⦁ Tableau Public: An open platform for public visualisations’ creation and distribution. ⦁ Tableau Reader: A free tool for examining and interacting with Tableau Desktop created visualisations.
How Are Calculated Fields Created in Tableau?
To construct a calculated field in Tableau: ⦁ Connect to your data source and launch Tableau Desktop. ⦁ In the Data panel, right click the data field where you want to base your calculation. ⦁ Select “Create Calculated Field”. ⦁ Enter the name for your new field in the dialogue box that appears. ⦁ Enter the calculation formula using Tableau’s built in functions and operators. ⦁ Click “OK” to create the calculated field, which will appear in the Data panel.
What Are Dimensions and Measures in Tableau?
Dimensions are category fields that divides the data into multiple portions. Qualitative attributes like names, dates, and locations can be included in dimensions. Measures are a type of numerical field that can be averaged, summed, or otherwise combined. Quantitative measures frequently show amounts, profits, or sales as data points.
How Can One Improve the Performance of a Tableau Dashboard?
Improving the performance of a Tableau dashboard calls several tactics: ⦁ Optimise data sources: When feasible, use extracts rather than live connections, and minimise the size of data extracts by removing extraneous information. ⦁ Reduce complexity: Eliminate as many quick filters as possible, streamline computations, and decrease the number of marks displayed. ⦁ Minimise the number of worksheets: Use fewer, more focused worksheets in dashboards. ⦁ Use indexing: To speed up data retrieval, ensure your database is properly indexed. ⦁ Aggregate Data: To reduce the amount of data handled, aggregate data in Tableau or at the source. ⦁ Limit the use of custom SQL: Steer clear of intricate custom SQL queries that might impair performance.
What Are LOD Expressions in Tableau?
Level of Detail (LOD) expressions let you calculate values at the visualisation and data source levels. They offer an alternative to the visualisation itself for aggregating data at various levels of detail. Tableau offers three different kinds of LOD expressions: ⦁ FIXED: Determines the values, independent of view, using the provided dimensions. ⦁ INCLUDE: Combines the values in the view with those in the provided dimensions. ⦁ EXCLUDE: Combines the values in the view that do not include the designated dimensions.
How Is Tableau Server Different from Tableau Online?
As an on-premises solution, Tableau Server allows companies to share, distribute, and collaborate on Tableau visualisations without compromising safety. The organisation must provide the necessary infrastructure and upkeep. Tableau Online is a hosted cloud-based solution from Tableau designed to provide all the sharing and collaboration tools of Tableau Server with less company infrastructure and maintenance required.
How Does Tableau Deal with Null Values?
To handle null values in Tableau, there are multiple approaches available: ⦁ IFNULL Function: Use the IFNULL function to swap out null values for a specified value. ⦁ ZN Function: To set null values to zero, use the ZN function. ⦁ Data Source Preparation: Use Tableau Prep or other ETL tools to handle null values during the data preparation stage. ⦁ Filter Out Nulls: By adding filters, you may exclude null values.
Explain How You Would Go About Creating a Dashboard in Tableau?
The following actions must be taken to create a dashboard in Tableau: ⦁ Connect to your data source: Bring in the information your dashboard needs. ⦁ Create worksheets: Make customised spreadsheets or visualisations based on the data. ⦁ Creating a dashboard: Click on the ‘Dashboard’ menu and choose ‘New Dashboard’. ⦁ Add worksheets to the dashboard: Drag and drop worksheets onto the canvas. ⦁ Arrange and format: Arrange the worksheets and include any required interactive components, filters, or formatting. ⦁ Add interactivity: To make the dashboard interactive, use filters, highlights, and URL actions. ⦁ Review and test: Ensure the dashboard delivers the required insights and functions as intended. ⦁ Publish: Share the dashboard on Tableau Server, Tableau Online, or Tableau Public as required.
Conclusion
A good understanding of Tableau features and functions is necessary to prepare for an interview. By preparing with distinct interview questions and developing thoughtful responses, you may show confidence and knowledge about Tableau. Being organised will make you stand out in the interview, whether talking about complex features like LOD expressions, reviewing the fundamentals of Tableau, or going through creating a dashboard. Consider enrolling in The Knowledge Academy Tableau course for a more comprehensive education that improves your knowledge and abilities.
