Barclays Global Service Centre Interview Questions and Answers

Live vs Extract in Tableau and why Extract is faster

• Live connection directly queries the data source while Extract creates a static snapshot of the data

• Extracts are faster because they reduce the amount of data transferred over the network

• Extracts can be scheduled to refresh at specific intervals

• Extracts can be compressed to reduce file size and improve performance

Yes, it is possible to update data in Tableau Extract.

• Tableau Extracts can be refreshed to update data

• Data can be added, removed or modified in the data source and then refreshed in Tableau

• Extracts can be set to refresh automatically or manually

Relationships are used to connect tables in Tableau Prep while Joins are used to combine tables in Tableau Desktop.

• Relationships are used in Tableau Prep to connect tables based on common fields.

• Joins are used in Tableau Desktop to combine tables based on common fields.

• Relationships are used to create a flow of data between tables in Tableau Prep.

• Joins are used to create a single table from multiple tables in Tableau D...read more

Standard deviation measures data variability, helping analysts understand data distribution in Tableau visualizations.

• Standard deviation quantifies the amount of variation or dispersion in a dataset.

• In Tableau, it helps identify outliers and trends in data visualizations.

• For example, a low standard deviation indicates data points are close to the mean, while a high standard deviation shows data is spread out.

• Using stan...read more

Dashboard Actions are interactive elements that allow users to interact with the data on a dashboard.

• Dashboard Actions are used to filter, highlight, or navigate to other dashboards or web pages.

• Steps to apply Dashboard Actions include selecting the element to apply the action to, choosing the type of action, and configuring the action settings.

• Examples of Dashboard Actions include clicking on a chart to filter the dat...read more

Use a parameter to filter data and create two separate tables, then combine them using a union.

• Create a parameter to select the number of top and bottom rankings to display

• Create a table for the top rankings using the parameter and the RANKX function

• Create a table for the bottom rankings using the parameter and the RANKX function

• Combine the two tables using a union

• Add a column to differentiate between top and bottom ra...read more

Sets are a collection of unique values while groups are a collection of related values.

• Sets contain only unique values while groups can have repeated values.

• Sets are used for filtering data while groups are used for aggregating data.

• Sets are used in Tableau for creating custom fields while groups are used for creating hierarchies.

• Example of a set: a set of customers who have made a purchase in the last month.

• Example of...read more

Collaboration is key; I prioritize tasks and assist colleagues when possible, ensuring team success while managing my workload.

• Assess the urgency of my tasks versus my colleague's needs.

• If my work can be postponed without significant impact, I will help.

• For example, if a report is due soon but my colleague needs data analysis, I might share insights quickly.

• I believe in teamwork; supporting colleagues fosters a collabo...read more

I would communicate proactively, assess priorities, and seek support to ensure timely completion of the task.

• Assess the situation: Identify the reasons for the delay and evaluate the remaining time.

• Communicate proactively: Inform my manager or stakeholders about the potential delay as soon as possible.

• Prioritize tasks: Focus on the most critical aspects of the task that need to be completed.

• Seek assistance: Collaborate...read more

Optimize data source, reduce number of rows/columns, use extracts, optimize queries, use filters.

• Optimize data source by removing unnecessary columns and rows

• Reduce number of rows and columns to only necessary data

• Use extracts instead of live connections

• Optimize queries by using custom SQL or aggregating data

• Use filters to limit the amount of data being extracted

Large data extracts in Tableau are handled by optimizing data sources, using filters, and aggregating data.

• Optimize data sources by removing unnecessary columns and filtering data before extracting.

• Use filters to limit the amount of data extracted.

• Aggregate data to reduce the number of rows and columns.

• Consider using Tableau's data engine to improve performance.

• Use incremental extracts to only extract new or updated da...read more